Need some advice... (LONG SORRY)?

I know I have asked this several times but maybe I will get more answers... Here is my issue... I have been married a little over 3 years to a guy that I thought was the guy I always wanted to be with.. BIG MISTAKE.. We met August of 2003 then didnt start hanging out until August of 2004. We started dating November of 2004 got engaged May of 2005 and then got married August of 2005. I had just turned 18 and he just turned 19. We were both having a lot of family issues at the time. I thought he was perfect and that nothing would change. Well he changed. We got married and then I got pregnant Jan. 2007 with our only child. He started accusing me of cheating on him and saying a whole bunch of BS. Rumors started flying around our town and it was just tearing me apart. I had our daughter November of 2007 and things just got worse. He took 2 weeks off to help me with our daughter well he never once helped me. He would stay awake while we were sleeping and then sleep while we were awake. We bought our house July of 2007 which was nice. Then things were getting worse again. He started limiting who I could hang-out with and talk to. I am a volunteer firefighter and he knows that I have always been close with a certain group as they are my brothers. He was fine with them. Then he started rumors about me and a couple of them. I told him that there was nothing between us and that we are just like siblings and so I stopped hanging around them. Well he had started accusing me again that i was Cheating on him. Well I told him that I didnt love him anymore. I did a big mistake and cheated on him with a really close friend of mine. He found out after the second time. Well that same time I found out he cheated on me before we got married. He tells me every day that I am a piece of **** mom and that I dont care about my daughter. My daughter is my life. Well now that I have like NO Friends as he dont allow me to talk to anyone or hang out with anyone i have no one to talk to. He tried to commit suicide last year and then tells me that if we get a divorce I get visitation rights only. in Decemeber I was at a friends and had one to many shots. He came over and started screaming at me and being an ***. I have been trying to build up the courage to tell him off. Well that night I told him. I have slept with the guy a couple times since the two times that he knows about. I told him I never want to see him again and so he went and cut all my clothes, my debit card and my credit card. I was young and stupid when I married this jerk. I dont have a job and I have been trying to get a job. Why are guys like this??? Why do they blame everything on the girl. Does anyone know how much it cost to det a divorce in Oregon???