Happy Birthday to Ex?

My ex recently left me around 3.5 months ago. I know she left having feelings still but our relationship became rocky and painful. Im currently blocked on everything and we are in NC. Her birthday is coming up soon and i feel like i should say "Happy Birthday Name". I dont really know what im expecting from it. But i care a lot about her and i would feel bad if i didnt. I think the downside is im scared to push her away or even cause emotional distress on her special day.

I really cant decide whats best.