<human>: Condense the text into a few key points

Recently, I've [23F] been talking to a guy [25M] and our relationship sort of turned into FWB. I say sort of, because we never had any type of sex (oral, etc). 

I knew him from high school, where he expressed how much he liked me and I've known he has had a crush on me for years. 

In high school he was very sweet and kind, and I really liked that about him. 

Recently, as our relationship progressed, He told me he wanted to date me and when I confronted him a couple days later, he said he didn't. 

I feel confused as to what he wants now, because I'm not sure if he's just trying to get down my pants? I've always known him to be a genuinely nice person and he was never like this before. 

I stopped talking to him for a while after the DTR talk went south, but he still messages me. The messages aren't like they used to be, and there is almost no effort being put into them.

Why would he even want to continue to talk to me all the time, when it seems like he doesn't give a shit? I don't know what changed because there was definitely a time when he cared. I'm honestly just feeling jerked around and I'm pissed off. I never knew him to be this type of person. 

Can anyone offer me some advice? I know you can't control people, so I can't make him care again. I wish I could get him interested again, or just turn the way he's treating me back onto him. It's not fair to play with the feelings of others.
<bot>: seeing this guy who I've known since high school. He screws with my head and I'm mad about it. What do you think he wants from me, and how do I respond to his messages?