What the **** is going on (goys can u help)?

me and my fiance have been together for 4 years and I'm getting mad depressed n all he wants to do is go out with his total head druggie mates and, leaves me at home, mind u might be pregnant and my hair is starting to fall out , there is so much more to it like he says he doesn't have to spend 24/7 with me i understand that but on the weekends, or even a little bit each night. we live together and i know he ain't cheating so that ain't an option. but its just how do i tell him i need him to be here for me, without starting an argument, cause his is very argumentative and if its starts an argument he drives off to his mates house id wouldn't mind so much if he new them but this is the 1st month and they are druggies