Am I over-reacting to his FB comment?

[Sandra L]

I've been dating this guy for about 3 months now but we're not officially "in a relationship" because we both recently got out of a relationship and don't want to rush into anything. However, we've been acting as though we are in a relationship. I've been over his place just about every weekend, met his parents, met his friends and it just seems like everything we do screams bf/gf. The other day one of his ex-gf had posted on his fb page " you know I am #1 on your best girlfriend list" and he "liked" as well as agreed to it and responded "yeah I'll give you that". His comment and agreeing with her actually hurt me. I admit I have a tendency to get jealous and that's probably due to my insecurities but am I over-reacting to his comment?? It really made me feel like I was nothing and like I have this standard to live up to and maybe that's why he doesn't want to be in a relationship with me.
Thanks for all the feedback so far. I agree with nakedninjagod in that we are not bf/gf so i feel like i shouldn't be complaining but it still hurts because i do have feelings for him. But I definitely see your point Kermit.
Looking forward to more comments..