Can someone help me with problems at home?

My parents have been divorced for a long time now, over 7 years. I've been trying to keep really strong but it's hard. My mom re-married, to a guy I like but bugs me most of the time and I just want her to be happy. My dad is dating a total ***** trying to make me and my dad's relationship worse between each other and he sees that I hate her yet he still dates her. My dad complains about paying child support, that he doesn't have enough money then he blows it on useless toys, like motorcycles, that he never uses. So now he is pressuring me to come live with him (I live with my mom) because I don't 'see' him enough. And I don't want to hurt his feelings but he is ruthless! And won't stop! I've recently gone through depression and I'm still suffering through it, I haven't told them yet. My school life sucks, because my teachers hate me, or they act as if they do. My grades are slipping and I barely talk to my parents anymore, we're getting into more and more fights, and our relationships are getting really tense. I hate this situation, I am a really strong kid, I rarely cry, but I've gotten to where this just hurts me so much I now cry every night or so it feels like. The sad thing is, is that I want to leave for college, and move out of the house, but I feel like it will never come. I've seriously considered running away from home MANY times. I still am, which I find sad also. Could someone help me, or tell me how to handle this?