It is daunting, mamaka, and the thing is, I think, once you realise, it is also the case that your life doesn't look the same again, because you change how you understand past/present relationships and enter future ones. On the plus side, once you work through it all, I believe you get to a more authentic and healthier self (and this is a better role model for your DC).
For me, it was a bit the other way around, I knew I had dysfunctional relationships which I struggled with, but after I left my marriage, I started to dissect these other relationships and recognise the patterns, and have ended up NC with parents and a couple of other people formerly close; and still working on boundaries with others. All of this takes time to come to terms with.
There is a book by Cloud and Townsend which is called Boundaries - when to say yes and when to say no to take control of your life (or something like that). It is written from a religious perspective, but in some ways, I found the religious perspective helpful, because themes like Love thy neighbour and Honour thy mother and father are so pervasive in society, whereas boundaries are not incompatible with compassion and love - it is about healthy relationships, and sometimes it is necessary to draw boundaries around unhealthy ones; this is not wrong.
"It seems that a lot of the emotion has to come out of a relationship to make it successful" - yes. My husband would respond to practical suggestions, as long as they were workable within his structured life, but firstly, I would have to make all the suggestions, and secondly, it was an emotional desert. When you are single, you don't expect emotional support; when you are married, you do. But as I said, I would leave longer term decisions right now, and focus on what you need day to day for you. It sounds overdue.