Most Helpful Guy
Maybe wants to show you he has moved on
Most Helpful Girl
My assumption is that he's trying to get a reaction out of you. However, if you're still really close maybe he thought you might be happy for him?
If you flirt with him at all he may be telling you that so you'll stop.
If you think he's trying to get a reaction out of you, then personally I wouldn't talk to him if I didn't have to. To me, guys like that aren't worth talking to.
You could always ask him what he meant by it if you are close.