You've come to the right place if you are looking for support. It looks like you've dealt with a lot in your life and a lot of the women and men on here have dealt with similar issues.
There are some really great threads on here and it's a lot of information, but I hope it helps you come up with a plan of action!
I'm not expert, I'm only 8 weeks in of my very first weight loss attempt, but I saw a dietician who worked out a very doable plan for me and I've been healthily and steadily losing weight - with all of your meds, maybe that would a good idea for you.
And I don't blame you about the surgery - When I was at my heaviest (which was probably more than 310) that was the first thing my doctor threw out there for me and I did a lot of research, and I discovered it was not for me. It's definitely not the quick fix the advertisements make it out to be, but I do understand for a lot of people that is their best/only option.
I wish you the best of luck and hope to see you posting!