Hi asheepywolf, I've never been in a relationship in my entire life, so please take what I saw with an
extra dose of salt. Hopefully I don't say something accidentally hurtful from my inexperience.

I felt I could connect with perhaps the situation with your daughter? I'm still relatively young. My parents broke up when I was 5 after a 6 year relationship, and I remember my father made all the
wrong mistakes. I didn't know it at the time, but I was so sad to see him suffering. I just wanted him to be happy, with or without my mom. At first he spent much time alone and was very depressed, and then he started up a relationship with a woman. Thankfully the woman was very kind and got him onto his feet, and even got him to go back and visit us often. It was good to see him happy and more sober. It would have been better if he had started attending therapy, and kept close with some positive friends. What if he got with the wrong person or friends? He was being very dependent on others at the time, which was totally understandable. Thankfully, he did start being with good friends and got on better terms with my mother.
But his loneliness kicked in and he flew straight back into my mother's arms without any requirements or questions from either side. Bad mistake. I had been okay with them breaking up. I understood, although sad, and I knew I would get through it. I couldn't stand them fighting, however. Maybe this isn't relevant to your situation at all, but I think keeping a respectful, calm relationship for now with your separated wife is great.
If this advice sounds a little inexperienced, than please know you're not alone. Many people on this forum have come from this situation and are now very happy, as you've been finding out. During recovery, this can also be a chance to learn more about your independence as well, and what you want from a relationship. If you don't have family and friends, you are also not alone. I myself don't have any family (my dad has already passed on), and for a while, didn't have any friends. I was really sad to be alone, but I started doing things and then began making friends. I've attended therapy, and will continue soon. And now I do have some people to rely on. I also eventually learned that being alone has benefits, such as more freedom, and following dreams. If you do drink, that's probably a recovery mechanism for emotional battles within yourself? Therapy would be a great way to start figuring that out.
If anything, I just wish you the best.

Please don't feel lonely.