Peter, I agree that rewilding/repairing our existing familial relationships is an essential aspect of building the foundation for a new culture - if we want that new culture to not have all the same problems as the old one. I don't think that in and of itself will do it, though. In other words, I think we also need to relearn how to live in true community with others (i.e. sharing our daily lives together, collectively relearning how to live sustainably and locally in relationship with the landbase, etc.). They can totally both happen at the same time - however, I feel that many (if not most) people's relationships with their families don't allow for living in a healthy community with them. First and foremost, I think this is because as hard as we try to heal these relationships, there is only so much one person can do without the equally active participation of the other - and in many cases, our family members won't be willing to do this. So this will preclude many of us from being able to actually live in a healthy community with members of our family.
For example, in my case I have a generally great relationship with my parents - as long as I don't challenge my dad's feeling of entitlement to exert authority over the rest of us. Calmly asserting myself as an equal to him - challenging the hierarchical arrangement itself - tends to result in all hell breaking loose. I feel that the only way for him to live in an egalitarian community with others would be to clearly establish rules for decision-making and boundaries of acceptable behavior, and consequences of non-compliance (so that he isn't just allowed to act however he wants with impunity like he currently does in our family). Honestly, I don't know if he would be willing to agree with this, and change his behavior accordingly (he has indicated in the past that he wouldn't). And unfortunately, since his behaviors are rooted in a particular worldview and way of relating to others, changing his behavior would require a massive reworking of these other areas as well. Would he be willing to commit to the major inner work this would require, and accept the guidance from others that would be necessary?
My dad is in no way unusual - I think he just exhibits the normal attitude and behavior for men his age in our society. And it's not like women don't also tend to have behaviors and attitudes that prevent healthy relationships - my grandmother and mother are also cases in point. Most intentional communities end up falling apart due to interpersonal conflicts, even when comprised of people with similar worldviews and goals (which most of us don't share with members of our biological families).
Realistically, as civ collapses people will be forced to start living communally with others - in most cases, the people who just happen to be around them. But because those communities won't be created with a common goal in mind, other than simple survival, I think most of them will end up being rife with conflict and unhealthy (hierarchical, abusive, racist, sexist, etc) dynamics. Yes, I think many people will learn, over time, how to work through those issues and get to healthier place. And I understand that the work of helping communities to do this is essential, and something that many people will feel called to do. I personally would do what I can in this regard, when the time comes. But my inner vision is to join with others in community NOW (not waiting until we are forced together by circumstance), living mostly primitively (actively relearning the old ways, adapted for our times), around a shared vision of building the foundation for a new culture to replace the old, that is based on healthy (non-civilized) ways of living and relating. In this regard we would be leading the way for those who will be forced into community later, by giving them an example to follow, and wisdom acquired through learned experience.