Me and his family having issues with my boyfriend.please help?

Alright so my bOyfriend and I use to hangout all the time.and him and his family use to be super close and about two months ago his old friend moved back and ever since than he doesn't want anything to do with me or his family and it upsets us both. They say he comes for money and leaves . & all he ever does is fight with me. He spends every single minute of his life their. Won't leave , && stays the night there everynight. Pretty much moved in. I think the mom is just taking his money and wanting him to keep givin it to her cause she always try's to get him to stay the night. He tells his Gma it's cause hE doesn't have rules. But he doesn't at home either. He Takes his sisters money too. Do u think he coulda got mixed up in drugs orlike just is tired of seeing us, or is confused? Help please. Sorry it's so long.