Something needs to change. You can't keep going on like this because it will wreck you. It's a vicious cycle you've gotten yourself into. Get out of it, learn to be by yourself, it's ok to do that and don't go rushing into a relationship until you're happy with yourself because it seems like, right now, all you have is drama over relationships. It's not healthy. See a councillor or therapist, work up the courage to do that and maybe they can help.
Courage. If you think that's really a difficult word to associate with or choose to live by then try not to think of it as being a person who can face all sorts of tragedies, evils, and fears. Instead, think of it as living without regrets. Not that YOLO crap that people spew, but sort of a "try, try, and try again".
"Who dares, wins" and "who cares who wins" have similar meanings. It's not about "winning" in life. That is, it's not about finding the perfect life since that would be boring as everything would be too stagnate. Making the most of your life is worth more than having a set life, set future, and set goals. All your failures, all your mistakes, all your successes, and all your dares are personal, little victories. They give you wisdom, knowledge, and a constantly changing and evolving life.
There are no wrong choices in life; every choice is a right one. You could choose to let things be or you could choose to do something different. Both are right choices since they would be right to you. You could take advice from us, take advice from friends (new and/or old), or take advice from therapists, counselors, and/or relationship experts. They would all be right choices. It's sort of an abstract idea, but as a person who thinks of parallel universes and stuff, it makes sense. It's weird. At this moment, I could be dead, I could be rich and unhappy, or I could be lost on a little island. All due to different choices in my and everyone's lives. Anyway, I digress.
Speaking of lives, this is your life; this is your story. You choose how to write it and nobody can interfere. So live and don't look back regretting (almost) everything. Personally, I've look back and I regret so many things, but from now on, I will never regret anything no matter how happy, sad, angry, jealous, lost, or indifferent I was. For everything I do now, I do knowing I did something rather than sit, think, and wait.
If you have to leave your friends to find someone special or someone who can help, then do it. Don't look back and if you do, look back smiling that you tried.
We have to start with little steps before we can walk, run, sprint, and maybe even fly. Changes are scary, but do you really like the way things are right now? If you don't, then do something about it. Just one step: a step in a different path.
I don't know if this is helpful or not, but it's something, I guess.