Is he purposely being impersonal or finally getting us out there?

My ex and I have continued to see each other even though we are dating others. We see each and text each other on a continuous basis. Why-I don't think either one of us want to stop seeing each other however I do want to turn this around so he is pursuing me again. Recently it was his BD and his present gf bought him and her a trip of which he went. When I saw the pictures on a web page I was shocked and terribly hurt! I contacted him right away and while he was on vaca with this person he automatically contacted me back that he was sorry. I did not wish him happy bd at that time because I was so terribly hurt. When he got back, I thought about it and did text him I was wrong for not wishing him happy bd as it was a significant bd. he text me back again and said he was sorry and that knowing how i felt that was the reason he did not tell me. A week later it was my bd and he actually posted happy bd on my web page. Thing is we have never posted anything to each other in public before. I do not know what to think - is he purposely being impersonal or finally letting it out that we do talk with each other? I am so confused!!! I want everyone's input, however men please tell me what you think!! Also should I just leave him alone for awhile and let him contact me? Will he contact me?