I am wondering why you stayed separate for the past year to save up money?
'Letting go' can be indeed a major trauma as you are trying to reject something that you once loved and to a small extent, probably still do. Of course he will try and win you back as that's what men tend to do, despite their shortcomings. The crux of this situation is really whether you are 100% committed to part from him and I understand how much emotional energy that takes. The other major consideration is whether you can both function independently taking into account money, work, housing and childcare etc so there is a lot to consider. And many people say that unhappy people should never stay together for the sake of children although of course many do.
You are clearly unhappy so perhaps you should simply draw a line in the sand with your husband and insist you continue to live separately ... agreed, people rarely change and you may find that living separately as a firm decision is your committed choice, whether that leads to divorce or otherwise. As we all know, life is rarely set in stone but for now your commitment not to accept him back is all you need. But with that decision comes a harder life ahead as you know so you know it will not be easy. But I always ask 'at what price happiness' so that is something to reflect on.
Remember he is probably as unhappy as yourself and hates his own demons. The big question for him, not you, is can he work hard to change himself?