How Can I Stop Having S3X With A Man Who Doesn’t Respect Me?

I am a 28-year-old woman. For six months I have been involved in a s*xual relationship with a man who does not value me. He is in the same social circles, so I see him frequently, and we only ever go home together when we’re out and have been drinking until the early hours with the wider group. Before I slept with him, he was much more interested, attentive. He’d be in touch. Now we are never in touch until I see him out and then find myself in bed with him later that night. I have told him repeatedly I don’t want to do it any more. I fancy him and want there to be an opportunity for something to develop. But he has said he does not feel the same way. I want to move on from this, but why do I keep putting myself back in this situation with him and expecting a different result? To make matters worse, he’s not particularly nice to me and takes great joy in telling people that he has slept with me, which really offends me. What can I do to put an end to this? I will still see him in a social setting and don’t want to excise myself from my other friends.