How do I do this?

I need out of my parents house but have no idea how to get away. Despite the fact that I'm 19 soon to be 20 they think they can control me. I've tried moving out before by they drug me back home even though I had just turned 19 and didn't want to. Now any mention of wanting to move out and they shoot me down by saying I "HAVE" to stay here just because I'm in college and yell at me if I try to talk back and defend my choice (I take all online classes so WTF is even their point?) They seem to think that I can't do anything in college without their help and that I'll drop out just because I'll move in with my fiancé (who I might add is very supportive of me being in college and makes sure that I'm on schedule in case I forget something). I don't have a job right now because I'm a full time student but I'd easily be able to get one and even then my fiancé has told me that whenever I do move out that he'll support me while I go to school but that if I want to get a part time job he won't stop me from getting one. How do I move out of my emotionally and mentally abusive parents home without them yelling and screaming that I'll never make it and that I "HAVE" to stay?

Side note: My mother has recently raised her hand twice at me like she was about to slap me so there's that too.