I think this is helpful - you are right it will be right in your face every time he texts you, whether he's trying to be smoochy and rainbows or whether he's turned the tables.

I know there's no official "diagnosis" but frankly from all I've read I'd be shocked if he wasn't one. I think it's a true personality disorder and as we all know, not curable, can only be made barely tolerable even if the person puts in a huge amount of work to overcome it (in the past he's done enough to keep you off his back)