roommate problems

I'm six months away from graduation and another five months after that is the wedding!!! yay!!! but i'm mad at my roomies. tell me what you would do in this situation....
So, my roommates refuse to pay for the cable and internet they use (which is in my name). they use it 24/7 and i never get the chance to sit at my tv to watch my cable. so i started taking the remote and then they hooked up a dvd player. I also changed the password on my internet til they decide to pay for usage. thing is, i changed the password for the internet last night. also, my roommate told me how much power is. I told her i'll get her power at the same time as i get her the rent which the earliest would be tomorrow. well, I walked in to my house to watch Heroes tonight with lee and pizza. we took over the tv, and she looked at me and said....."do you have power money". I told her i didn't buy the pizza because my check doesn't go through til tomorrow. so no. and she got super pissed and huffed and puffed the rest of the night. they also don't respect my stuff. On sunday I came home from lunch with lee and the screen door and front door were wide open. I had my tv, computer, movies, cable and internet stuff, and lee's computer sitting in the front room in plain view. I mean seriously, who leaves a door wide open when they aren't home!!!! they are always moving my stuff off my table and couch and putting it on the floor. they refuse to be decent people. over the summer whenever lee and i would make dinner they wouldn't thank us. we would make enough for all of us plus some and they would cook for just them two.
Now the chick and i were really good friends...then her boyfriend moved in. her boyfriend is a d***. He is the reason for her attitude garunteed. argh. I don't know what to do. I can't move out. Although i want to. But with my cat its hard to find a place cheap enough. I don't know what to do. I've talked to people out here but all they say to do is to move out. loose the friend and move. but I can't simply just pick up and leave cause the cat. HELP!!!!!!