Alright my girlfriend's parents hate me passionately. what should I do!?

My girlfriend and I have been together for several months now. (six) her parents started out being alright with me, then we had an awkward confrontation after she told them we had sex...
Things were fine still though.
about 3 months into the relationship I got hella drunk and cheated on her with another girl.
HER and I worked it out, and are still happy together, and even stronger and more open than before, but her parents found out and they want to set fire to my house for christ sake.
Her and I are still seeing eachother, but as I gather they get in arguments about me. ( pretty intense ones ), because they don't want us to see eachother. And just recently her Dad confronted me face to face and told me to stay the F*ck away from his daughter or he would have me arrested, knock me out, etc. Her mom threatened me with a restraining order... and I even had my own mother call to speak to them and they hung up on her. They are very immature for adults, and think they know everything, they also try and control my girlfriend's life. ( She's 18 and I think she should make her own decisions... ) But they have the car, and they are completely in control of all the pieces.. What should I do? I've tried speaking to them I get shuned.. I've tried reasoning.. I get shunned..
I haven't lost my cool yet, or been rude or disrepectful, and I'm about ready to give up, because I don't want to see my girlfriend get hurt by her parents any more. ( Emotionally ).

Any suggestions or advice would be Much appreicated.

hey ok I can c were they would b up set because you did f*ck her and then cheated on her but holey sh*t I dont balme you 4 not wanting to c her parents but my god wow I dk if you have tried this or not but sit down with your g.f and BOTH of her parents and try 2 starghtin this out and you r 100% rite she is 18 and should make her own Decisions! just sit there with your g.f and her parnets and tell them hey I f*cked up and im sorry for f*ckin up can we just put this behind us!

wow thisis a hard one. I know wheere youer comming from with hr parents. My brothers ex parents were like this and he ended up breakin up with her because he got sick of dealing with them. DO NOT lose your cool I can see howd you want to, but dont itll just make them hate you more! What you should do is have your girlfriend sit them down, (U SHOULD NOT BE THERE UNLESS YOU WANT AN ARGUMENT ON your HANDS)and tell them, im 18, im a mature adult that can make my own decisons, and if you do not approve of the man I love than I am going to have to leave here and never return, and never speak to you again. All the parents are doing is trying to spilt you to up because you are freeing here of the chains (her parents) that have been holding her down all these years. They get weird when they think about not having her under their thumb. They need to give her her earned freedom, and if they dont then she needs to take some course in action, decide whats right, and do it herself, if you try to talk to them itll make them just angerer. Good luck my friend.

I dunno... but the same thing is happening to me... Me and my girlfriend were going out in 7th grade but then we broke up and hated eachother for the rest of the year... we made up in the next year and now we are going out again in 9th grade... Her parents started hating my back in 7th because we hated eachother... but then after we made up they continued to hate me and never really gave me a chance... the next reason they hate me is because in the 8th grade yearbook I wrote something really personal and they read it (what the f*ck its her yearbook) and they freaked out... Finally this year 3 kids told there parents (these kids are such b*tches)that we were feeling eachother up and then their parents called my gfs parents... after this her parents had her 'break up with me' but she didnt really... we just told them that we broke up... also when she had to break up with me her dad spoke to me on the phone and told me that im not allowed to go out with her daughter... now they just found out again that we are going out a few weeks later and they are freaking out yet again. I have no idea what to do because her parents are starting to get school into it (theyre trying to get the security to not let us be together) and they mite call my parents (who no nothing aboutANY of this) and I dont want my parents to find out because it would be the most AKWARD conversation ever... We havent gone past feeling eachother up and I no were only 14 (almost 15) but I feel that her parents are overreacting and that they need to give me a chance (also her parents are really screwed up and dont even love eachother which shows that their advice doesnt really mean anything). If anyone could tell me what to do I really really need it... thx