why is he acting like this?

I have been good friends with this guy for a while now and have started to catch feelings for him which I am trying to ignore. He asked me if I would sleep with him not once but thrice each time I said yes but it never happened. Anyway I told him how I felt but I didn't want to complicate things now he has completely cut me off and ignores me when we are out( we mix in the same circles) he has done it before but we tend to start talking again after a few days this time it has been 3 weeks. why is he acting like this if he has no feelings towards me?