Sorry to hear that you haven't found something that was helpful for you and it was all aimed at weight gain.
Like everything different things work for different people. I am passionate about eating disorder recovery and am in recovery myself from binge eating disorder and bulimia (switched eating disorders!). I've used multiple different strategies which include counselling, support group where I hear other people in recovery (international one is Overeaters Anonymous
), food diary
I also write quite a few blog posts A KNEW YOU
on eating disorder recovery and related topics.