This guy I know said we could be together and then he ignored me after I wouldn't strip for him online?

If he can't respect you then really he is not even worth giving a second chance to, he is trying to make you feel guilty for not wanting to do what he wants, that is not the way healthy realtionships work, it is about accepting the person and caring for the things that are important to them like values and morals, and not just about him wanting to get off on seeing you nakes, the guy sounds like a jerk.