Can someone help?

My ex and I broke up 3 months ago, he went back to his previous ex 6 weeks after, he kept snap chatting me everyday and the odd text message here and there until I deleted him off everything because it was setting me back each time. He’s recently tried to re-add me on Facebook a few times but I’ve ignored all his requests but at the same time he’s posting loads of posts with his ex/gf - can someone give me an insight as to what he’s playing at?? And why he keeps trying to add me if he’s moved on?? Thanks in advance.