HELP!!i need serious Help!!!!!!!!!!!!!?

My Bf and I both go to school still.How do I tell him I don't like some of his friends.He knows that i love some of them 2.I really love him but i heard that he did really y things 2 another girl in a motel room that was my friend.He admitted to doing it as well.Can I trust him.I love him so much i just sometimes in my head pretend that i go over to him and grope his *** and we have in the cl room.how do i get that from a thought to making it happen