I miss him so much it hurts...help?

One, get out in the sunshine, sweetheart. Vitamin D is Physiologically an immense help for depression. Sounds like you need to resolve this guy in yourself and your psyche if you want to be level, and have any say in where you two end up going. Is he being evasive, or disinterested? It sounds to me like you're giving him a bit too much of yourself, you get to decide for you, no one else. My advice is to get out there and experience other people to build up your own interpersonal character. There's a whole world out there!! And Tristan is probably going to be in this world for awhile, so feel free to go out and find yourself first.