Is it me ??

Hi, Just hoping for an opinion out there or generally just need to get this off my chest. My husband has had a really difficult time with his ex wife as regards seeing his kids, and she's been a right arse. Things have improved over the last year but in his words... he was never going out of his way to be friendly again !! which suited me as she'd been not only awful to him but not very nice to myself either ! Although they are not friends on facebook their two boys are with both of us and lately he's been liking alot of her comments in relation to the boys threads. I did tell him a week ago that this got to me a bit particulary since he will not tolerate me having any contact with my ex (granted he's been an arse to). On thursday eve she'd loaded a couple of pics of her and the boys on and tagged them in so that he could see them... he put "lovely pic" on both of them.. because in his words.. they are lovely pics of his boys and their mum ! It got me because she was in the picture with them. I reminded him of how he was never going to be friendly etc..but he just doesn't see it. I know if I'd done the same on a pic of my boy and his dad he would not have been happy !! different rules apply and its just so unfair..we haven't spoken since that night and I'm feeling so down about it. It all seems so petty when I'm reading this but obviously from somewhere I have had insecurities. I think because he's gone back on what he's said in the past and thats all forgotten on his part.
He is a good husband and we've been together for 4 years now. We used to be engaged 20 years ago but we split up and got back together after we both divorced. He is also quite critical of my son (he's 13) just constant little remarks which he says are in jest but they really get to me sometimes. Particularly when his two boys come to stay (16 & 14) and are fussed over.