He doesn't care for me and doesn't trust me too much anymore, so why won't he block me or remove me from his friendslist?

Maybe because — and I don't mean to be cruel here — it's because he doesn't care about you. As in, you don't matter to him enough for him to do that.

Which suggests perhaps you'd be better off doing the same to him.

To keep an eye on you. "Keep your friends close and your enemies closer".

Can’t control what he does but if it bothers you, you can always block and delete him.

Games and not the fun kind

What did you do?

in case he gets horny

he's keeping you as a side piece most likely