Maybe he’s just not ready for that commitment? Maybe he knows he might hurt you, and just doesn’t want to cause you pain?
There are so many reasons why he may not want to be with you at the moment. Ask him why he doesn’t want a relationship with you. That’s my best answer. Every single guy is different, perhaps you’ve gotten played, so you think that just because he says “I love you” and doesn’t want to be with you, you’re assuming he’s playing with your emotions. There’s so much you don’t know. Just ask. And he will enlighten you.