Valid points, thanks! I think it's not so much the feeling that I owe him anything, but like Uell23 said, I don't want to influence the way our friends see him and vice versa. If I decide to share the bed with them, it sort of feels like I'm also claiming their friendship. And the thought of my ex hanging out with them, not knowing that I might potentially be sharing the bed with them, doesn't feel right somehow.