I was in a similar position to you (I hope dang does not mind a throwaway being used for such purpose). You're actually better off then where I was at the time, because you've already traced it to childhood issues.

I could feel myself sinking but I didn't know what was causing it. I started getting caught up in drugs, alcohol, etc., and I knew that it wasn't me but at the same time like a hydra if I cut off one vice suddenly another way to "cope" would surface. I now understand where the traditional notion of being "possessed" comes from, it's not possession by an external force but possession by your own inner demons that simply can't be suppressed any longer.

You are right that most therapy was useless, they don't address the core issues. I will suggest the book "The Presence Process". I'm sure you're tired of self-help books, but this one is the first one I've read that actually "pulls up the weeds of trauma" out of your mind (actually it can't do such a thing and it even says so, what it can do is pull back the facade to allow you to feel for yourself where the weeds are and allow the mind's natural garbage collection mechanism to take over. This isn't an easy process, as the shadow self surfaces you're going to feel worse). And what you wrote about issues being "largely the same ones I dealt with 5 or 10 years ago" is actually almost straight from a chapter in the book, it calls it the "7 year cycle" of resurfacing trauma.