The child that is groomed within the hoarded space is a child that is subject to many external stimuli. Excess information overloads the central nervous system which leads to feelings of stress, tiredness, low energy, irritation, anxiety, depression, procrastination, among others.
These have a tremendous impact on the child's behavior, mood, psychological stability, in the ability to form healthy relationships based on a healthy identity, the ability to utilize their space for activities, tasks and to bond, among other difficulties.
The problem is not just regarding the space that is disordered, impeditive and frustrating, but that the hoarder lives there is the direct cause of it all. No matter whether the hoarder says it's not their intention or that that have a good excuse, or that they'll fix it, in the end the result is the same - the child is still locked in that dynamic with a person that is incapable of maintaining a practical system.
The first problem of the CoH (child of hoarder) is the hoarder himself; the second problem is the hoard as it is; and the third problem is that situation and dynamic impacts daily activities and relationships. From removing the ability to bring colleagues for school projects, or friends for leisure, or even to establish romantic relationships, to not be able to change the configuration of the space to use it for different projects or to hold family gatherings and dinners, the hoard narrows down dramatically the number of possible social 'games' that can be played with the house.
These are just the spatial and relational problems, but over time the hoard brings other problems that begin to stack and create a 'snowball' effect.
If the hoard is not overcome or bypassed it will become a burden that will affect the natural development and phases of the CoH's life.
By making the CoH having to organize his life around the hoard, with all its paranoias, it heavily interferes in decision making quality and in the opportunities and solutions available to the CoH. This will narrow the development and lead to stunted growth.
Note: I advise any person trying to understand hoarding disorder through the narcissism lens. It will provide an essential template to understand hoarding behavior. It also stems from PTSD/CPTSD and it shares a lot of similar behaviors, symptoms, and dynamics.
Since the disordered parent creates a 'paracosm' within the hoard it forces the child to incorporate this parallel reality and create a split persona - the hoard persona and the outside persona. This split creates a false sense of reality since it forces the child to lie to everyone outside of the hoard to avoid shame, presenting a 'false-self', which acts like a 'double agent', leaving the real self behind in the hoard.
The greatest advantage between narcissism (NPD) and Hoarding Disorder is that many of the dynamics in narcissism are literally 'materialized' in the hoard. Once you start to notice that the pile of objects is the hoarder's mind turned inside out it becomes clear why it has this presentation.
The hoard is a shameful and terrified call for help by the hoarder. The hoarder will obviously rebel to any attempt to help him but, nevertheless, this extreme behavior is an outgrowth of an insoluble problem that goes well beyond a logistical challenge.
Naturally, any schism in the personality creates a 'cognitive dissonance'. Two sides that have began to have different lives will eventually create problems of integration internally, but it will also create difficulties managing two working personalities that don't clash with one another.
Each child is different, and I wouldn't presume to know how each person deals with the hoard emotionally and how they take measures to engage with it or escape it. But any person that stays in a severe hoard long enough will experience many of the symptoms previously mentioned. From stress, to anxiety, to shame, to disgust (even with oneself). All these primary emotions and feelings degenerate into second order states of consciousness that enhance the CoH experience into a more complex one. Stress can push the experience of reality into one of derealization.
The greatest challenges of the CoH is not having sufficient information and having to move through life without sufficient tools to ameliorate both their emotional state, and their situation and environment. Two routes must be worked on: the emotional stability side and restoring the environment to decent livable conditions.
Looking at the emotional toll and the destruction it leads to in the nervous system I have to say that, specially for underaged children, you might want to consider alerting the authorities to trigger lawful action due to negligence. It's not an easy move, and it certainly is not an action without consequences and costs but looking back it might have been life changing. See, the thing about the shared fantasy is that it will make you conspire against yourself for what you clearly see as noxious to yourself. It's insanity. It's sick. And it's very dangerous for your health and for your future - personality development and work.
The worse you let it get, without either taking serious measures or escaping altogether, it will undermine you every step of the way - your goals and relationships. This will breed frustration which will foster despair, anxiety and depression. It doesn't end well.
Alcohol and drugs are easy escapes that can serve for a time mitigate some of those feelings, but they not only don't deal with the root cause, they will progressively serve less and less to deal with primary feelings, and start masking secondary ones. And, in the end, you'll have to deal with the natural drawbacks of any chemical addiction. The better alternative is to have a clear mind at all times and use your mental resources and energy for your preferred strategy.
If you have another parent outside of the hoard, make the hoard situation evident and try to live with the healthier parent. Even if you have another family member that can help you you can try and take advantage of that opportunity. But in my experience the hoard doesn't quite leave you, regardless of where you go. Unless you are prepared to cut relations with the hoarder parent and not hide their pathology from the people in your life, it will use your goodwill against you and make you their agent. The hoard is so sticky because when the hoarder 'self-trashes' he also trashes his own identity which spills onto the people in their inner circle, soiling them. And don't make the mistake of assuming this is a secondary collateral accident; this was chosen every step of the way. They pull you down with you on purpose - for that purpose.
It's also a mistake to see the hoard as simple spatial assault. The hoard is boundary breach of your identity. And it will make you shameful because you were vulnerable enough to take it.
It doesn't matter how many times they'll say that it wasn't their intention or that they'll change. It will be too late. By then your life will be in shambles in every regard that matters, and he will have succeeded in taking you down with them.
The hoard isn't just a dictatorial landscape where trash and chaos are elevated with literal edifices to those principles, behind it is its supreme ruler - the hoarder. The hoarder gives everything to the hoard; is a slave to it, and at the same time is its God.
One thing you must realize is that hoarders have a psychodynamic that is solipsistic, materialistic, positivistic, and so they externalize their psyche without even realizing it. They create an external landscape that reflects their disorganized inner world and they expect you to become its subject through the external barriers and impositions.
As you live in the narcissistic space created by the hoarder you will become shaped by it and will become calibrated to it. But this is extremely emotionally dysregulating. The switch between the hoard and the outside world is very abrupt - having radically different rules and 'selves' you must manifest to operate within them. This implies that your 'self' will be stretched thin and eventually broken.
Make no mistakes that bringing up a child in the context of a hoarded space is neglect - physical, emotional, and psychological abuse. Do not doubt this for a second. Even if you understand the conditions that led the hoarder to that position and sets of behaviors, even if have some empathy or some gratitude for the good parts, do not, and I repeat "do not" let yourself be swollen by the stockholm symdrome. The momement you give an inch inside your mind is the moment you get complicit with the hoard and the hoard's advances in your mind. Just like narcissim it's a battle for your mind.
You are not less. You are not an appendix. You have to center your mind and priorities in yourself. Anything other than this is self-neglect. You collude with the hoarder for your own demise. You let them swallow you, just like a black hole (astronomical singularity), when you are past the 'event horizon'.
Even if you can lead the hoarder to rehabilitation of their behavior (which is possible), not only will it take a very long time - because it's on the hoarder's convenient time schedule - you won't be able to fix the underlying psychopathology originating the hoarding behavior, which is narcissism.
'Narcissism' is like a tree that grew up skewed or shrivelled - it can't be undone. Maybe with some serious pruning you could restart their growth in some stable conditions, but it won't ever rewrite the past. What's done is done. Narcissism has deep original wounds with the dynamic between the child and the primary caregiver and these are not going to simply get fixed. So you must manage your expectations regarding what you can and can't do.
What the hoard does to your living space is remove possibilities. And when you look at the hoard after a hard day of studying or work it looks like an impossible or overwhelming task. But you must realize that in order to go from a disorganized space to an organized space you must have the principles and skills to maintain a space, without letting it degrade. So, it's imperative that you focus on taking extreme measures in strategic waves.
If your goal is to leave you must go 'no contact' - which includes several strategies advanced by Sam Vaknin to bar any possible room to give the (narcissist) hoarder any encroachment into your life. For this you will most likely need financial resources and help from people you can count on to detach from your hoarder parent. But if you can't imagine how you will muster the emotional, psychological, relational, and material/financial resources to go through with your emancipation then all you're left with is to deal with the reality at hand.
This website is mostly focused on the latter because it's closer to my experience. In my experience, the hoard follows you around. It taints your image, your life story, the boundaries that were breached and, the hoarder alienates every possible attempt at a different life you try whether you stay or don't. The hoard lives in your mind much like 'introjected narcissist' in the 'object relations theory'. In order to change your inner 'objects' you must change them on the outside, or find a way to change how you relate to them. Neither are easy but both are somewhat possible.
Managing the hoard is essential because it's the source of your inner schism that will produce all negative symptoms you might suffer through. By fixing the hoard, that split will start to merge back up again, but not without cost. The longer you don't fix the situation the longer it will affect your abilities, your attention, your mental and emotional stability, and the longer it will deplete you of energy. Depending on the level of the hoard it will leave you with psychological scars that will haunt you for as long as you'll live.
People around you won't understand it. They won't understand why you are failing at work or school, why you can't get a girlfriend (or won't), why you push your friends away, why you are energy depleted, why you miss opportunities, why you lie, why you are depressed and anxious, why you have brain fog, why you are unmotivated, why you feel hopeless, and the worst: why you can't for the life of you tell anyone about your situation. If this last point doesn't clarify the cultish and 'captor-kidnap victim' relationship then nothing will.
The hoarder will isolate you more the longer you'll adhere to his side.
What's left at the end of your time with the hoarder is a cynical person that can't trust anyone, is overly sensitive, and doesn't feel supported by the hoarder to build a healthy life.
When you see what a person is capable of, to care about themselves, even if it destroys you, you begin to look at human beings differently. Human nature is no longer one of goodness (alone) but of extreme wickedness, especially by the people closest to you that owed you the most. This reorganizes you forever.
It's hard to say what kind of person leaves the other side but it's not a person that will see intimacy as safe place.