Ex using me for sex

So my ex and I broke up in December and we hadn’t talked for a couple of weeks because he just became so distant with me until about a week ago he contacted me claiming he missed me and wanted me back. I naively believed him and started to talk to him again although I was skeptical at first. But now as we started talking I just realize all he’s using me for is sex and we’ve exchanged some pictures here and there and I admit at first I wanted it too but now I just realize how wrong and hurtful it is. He’s always asking me to meet up and that everything will be fine he just sees me as a friends with benefits type of thing. Mind you we dated for almost 3 years. Never did I think he’d say a such thing to me. I texted him asking if what we were doing also made him uncomfortable and the hurt I felt when he texted me back is “I’m just gonna have sex and leave” um what. Before y’all comment that I’m really dumb for letting it go on, it’s tough especially when the breakup is so recent and it’s easy to attach yourself to someone again but it’s the fact that he claimed he missed me and everything and now all he sees me as is an object for his pleasure. Any advice on how I can just move on from this it hurts?