What do you think he is doing?

2-3 months after a light rejection(we didn't date or do anything physical) I've experienced the cold shoulder, unfriendliness, hostility(in the jokes-though my fault because he probably thought I didn't care but I did, I just never called him out on it) and (DISRESPECTFUL comments that came off as innuendos()) & with small amounts of "kindness"(very rare). One day he was making fun of me and he went a bit too far. He finally got to me and it showed thru my actions, He noticed the next day and wondered if it was because I didn't like him(he didn't take it so seriously, though). The next few days he became increasingly nice and finally told me that he was going to TRY to be nice to me and that he liked me(not romantically, in my opinion, and his words DO NOT match his actions) and didn't want me to think of him as a mean person and he wanted a "new start". I have a HARD time believing you can go from disliking someone and being mean to someone to all of a sudden being nice and caring about what the person thinks of you. I don't know if I should cont. ignoring him or take his word because he might turn around and act like an donkey again. And why the sudden change?