What does it mean if your ex-boyfriend texted you to wish you Merry Christmas?

My ex broke up with me about 4 months ago. We have not spoken with each other ever since. But last month on Christmas Day he sent me a text wishing me & my family a Merry Christmas, and I was very surprised. So I was kinda expecting him to text and wish me a happy birthday on my birthday, which is a month from Christmas. But he didn't.

I'm just getting more and more worried because I know he recently got introduced to this girl who I think is pretty compatible with him (I found out through facebook). I know you might think I am stupid for still hanging onto my ex, but I just can't seem to let go. I feel so helpless because I really don't wanna lose him, but I can't do anything about it. It's so painful.

Do you think there would still be a chance of getting back together...?