My W's b-day is in 7 days. I have no "plan" to contact her or do anything "for" her.
I am doing this NOT because I'm angry with her or trying to make a point. It is because that is pretty much me. I don't give my bff's gifts or cards and generally I do not make contact with them intentionally. I simply acknowledge it in the moment, if the opportunity arises.
So IF there is contact with my W on her b-day, I will probably offer b-day wishes. But I'm not planning on anything.
If she was simply someone you know, a co-worker or acquaintance, what would you do? Because that's all she is right now. Would you even know that it's her b-day?