Been there, Tim, and know how easy it is to get stuck in a rut. My cure was travel. I've done it a few times now where I've been peed off with my surroundings and life in general so I just sold up and hit the road jack. People have said to me don't I get lonely travelling alone, but I've always found it relatively easy to make new friends along the way.
Look on the bright side - at least your young, free and single. You got nothing to tie you down. Believe me, life's even worse when you're stuck in a relationship you're not happy with and can't see a way out.
What's that saying? A change is as good as rest.