If you are both married and have children, suddenly one day your first boyfriend who broke up for more than ten years sends you a message asking how you are. How would you feel?

I think it depends on the individual's mentality. If it were me, I would have forgotten him completely and had no feelings for him, so I would take his short message as a greeting from an ordinary friend, just like a greeting from a colleague or classmate, and give him a chance to ask me (provided that he didn't hurt me too much), mainly depending on how I treat this kind of thing! I hope this helps.