I agree with Christina. The kindest thing you can do is to break up with him as gently as possible if you aren't interested in pursuing this relationship any further. It's better to do this than to lead him on. Your mom isn't dating him, you are. Keep that in mind. If you have already told her that you don't want to date him any longer, then that is your business, not hers. I would also suggest changing the passwords on your accounts as well. Good luck.