I really don't know... try to find something that diverts you?
Do you have any interests that you can pursue? Make more of them perhaps. It doesn't need to be anything super special or important. You're not trying to save the world, impress anyone or sell anything. Just something to occupy you, and try to ignore that you might feel it's pointless. Just let yourself by taken over by it.
I try to keep myself occupied by writing. I'm not trying to write a book, or keep a journal or blog or anything. It's simply to pass the time and to divert my mind, something I can lock my mind into. I can spend hours reading over what I've written then rereading, rephrasing, correctly grammar and spelling. All pointless really, in the scale of things, but it works for me. Sometimes, as a break from that, I write little programs on my computer; they're not anything special but they do sort-of useful things for me. That can keep me occupied for hours, tires me out before I go to bed.
I can't do alcohol or drugs because they really don't work for me; I just feel worse.