I don't know what to do anymore...

My fiancee takes off drinking and doesn't care that I lothe it with a passion... I don't know what to do about it.. I'm scared to leave and being alone again.. I have a whole back story but it's too much to type, I hate his aunt that talks him into drinking all the time, she rubs her ass on him and hugs up on him like he's her boyfriend not her nephew. Who does that?! I have told him time and time again that it's going to end up bad between me and her but he won't believe anything I say... help...