It's been half a year since I broke up with my ex-girlfriend, but I haven't been in touch. Neither of them found another object. Today is her birthday. Can I send her a blessing message? ...

You should be clear about this. The question is how you still feel about her. Personally, I think that if you want to get back together with the other person, you must find an excuse to send her a message quickly. You must seize the opportunity. If you just want to bless her, that's fine. In short, it is no problem for you to send a blessing message for someone else's birthday under such a suitable situation. Of course, if you really think that you only had it in the past, then this short message will be sent normally, and you don't need to remind the other party of any untrue assumptions. You know that she hasn't found someone yet, which means that she still cares about her. I still remember her birthday, which means that even if you broke up for some reason, you still clearly remember the happiness with her. If so, I think you should summon up the courage to start over. Feelings, you "seriously" lost this thing once, and you will truly appreciate the preciousness of feelings, right? Call her at 0 o'clock today or be romantic. In fact, many things are not that you don't know how to do it, but that you are honest with yourself!