I don't know what to say for sure, but sounds like she is just trying to be "nice" to you because of your b-day.
My W left a week before my b-day and called me on my b-day to wish me a happy b-day.
She is still gone (2 months) and doesn't show any interest in getting back with me.
I think that maybe in your and my case the LRT (last resort technique) is the way to go.
We'll see what other, more experienced people have to say.
In the mean time, just hang in there and I don't recommend responding to her message right away or she will think all you are doing is waiting for her to contact you and that you haven't moved on with your life at all.
