So my ex left me for someone else (we were engaged) and long story short he's been trying to keep contact with me by adding me to his PS4 friends list after deleting me when we broke up and he sends me invites to game out with him and adds me to party chats and asks me to go on the mic and game with him. I figured why not and just gamed with him a bit but he kind of flirts with me and quots sayings we use to say together and bring up memories we had and goes on saying "good times" and seems to laugh at all the jokes I say even if they aren't funny. When I don't accept his party chat request he messages me telling me to go on the mic. His mom also said he seems to show off more when I'm online with him and is super calm when I'm not on with him. Why is he flirting and doing this while he's with a new girl?