(((AF))) oh my, that is heavy... I'm so sorry about these things you need to deal with. I really like EndGame's analysis above also. Of course it's your personal evaluation how much and in which ways you identify with these kinds of observations. I personally am always very interested in getting into these kind of connections between events, relationships, feelings, whatever all over the map and past-present, but surely it can be difficult to handle it.
I also understand more and more the things you said here in the beginning, in the first months when you started posting on SR. It all makes sense and I'm very glad that you are taking advantage of this board to deal with these things, and also that you are getting professional help. I believe that you will do a great job processing it -- you may not see the progress from the outside, but it's very clear for me that you are doing some good work already. Of course it's not easy, simple, fast, or linear... I think that's most often the nature of these processes.
I am with those that suggest that you don't stop posting about your family issues and your related feelings here. I sometimes feel that I don't want to talk about disturbing stuff in front of many people (even on an online board) because I subjectively think it just keeps problems alive instead of closing them and moving on, but I think this is only really effective when we have done a great deal of work and closure with them. I think it's great if you talk about these things especially when the feelings are associated with urges to drink.
Btw, I don't think it's bad to be in therapy for a lifetime if it helps, and especially if you like it. I can totally see myself do the same, even if it's not about digging into old troublesome issues so much but just part of regular maintenance (which I am far from at the moment, so more hypothetically), like getting periodic physicals from a doctor etc. You don't need to see yourself as someone carrying pathologies at all.
Again, good work, keep it up
