I'm not surprised it was just left on read as we haven't really spoken since a couple of weeks after the split which was about 10 months ago. Before any of you say oh just get over it, we were friends or had known of each other for about 7 years before we got together and that friendship state is all I'd ever want back if anything (I wasn't even sure about sending that message). We aren't friends, we aren't enemies, we see each others social media updates regularly with no hidden feelings (Well only able to speak on my part). Things had improved between us over the first few months of the split but was still odd if we saw each other in person with mutual friends, don't know if that's improved since.
Most Helpful Girl
Look, you could have never sent it and always wondered what could have happened if you sent it. The worst thing that could have happened is her not replying but at least you know now. Try to find the positive in it and just acknowledge the outcome and move forward from it. Don't beat yourself up about it too much.1
Most Helpful Guy
It wasn't stupid, it's never stupid to wish someone a happy birthday. You might say that it would be naive to have expected much to come from doing so, but you can still be happy that you were nice enough to do it. If she doesn't respond then fine, life goes on. You've still done a decent thing.2