What would you do?

I transferred to a new school, and when I first arrived, this person was the one who introduced me to several other people. After knowing each other for about a year now, I’ve started noticing some odd behavior from him.
Sometimes he’s friendly, and other times he isn’t. The only reasons I still walk around with him are:
1. He was the first person to help me around when I was new.
2. He’s friends with one of my friends.
What bothers me is that his actions can be pretty disrespectful at times. He makes random jokes at my expense and comments on what I do or wear. He doesn’t even say hi to me, but he greets the people around me — the same when he says goodbye. Yet, when it’s just the two of us, he still chats with me, which makes it even more confusing.
I don’t like this kind of friendship where I feel uncomfortable or disrespected. I’ve thought about distancing myself from him before, and when I did, he still came back and started talking to me again. Part of me wonders if there’s something going on with him that makes him act this way, but then again, he doesn’t treat other people the same.
Right now, I’m considering distancing myself even further, but I’m unsure if I should or if I should just let him continue acting this way.