Bare with me this is long....

I've been with the same man for 3 years about and he is my first serious relationship, I love him but I'm not in love with him and I don't see my self marrying this man ever. He's my fiance. The thing is he is mentally abusive,we have 2 boys. I want to leave but i don't know how. There's this guy I know that is so pissed at how my fiance is treating me, well he wants me and my boys to leave one day with him so I can get outta my situation. Would it be bad of me to do that, and to just rite him and note of how I'm feeling and that I don't want to be together anymore. My fiance will be gone when me and the boys leave, I'm only doing it this way because we have gone to break up before and he pulls me back in by manipulation. Please help Me! I just don't know what to do and I just want to feel safe, loved,and no the my boys are taken care of. My fiance also does not work, have a driver's license or know how to hold a job.