Ex reaches out after 15 years?

I’m happily married with kids. My first girlfriend and I separated 15 years ago. I never looked back. I heard she got married too. But I got an uncanny text from her a few days ago asking how I’m doing, that she’s doing some “reflecting” and feels bad. Why now? Should I do anything?

Updates
+1 y
Talking with my wife i agree no response is appropriate here. It just seems odd and honestly kind of selfish of my ex to resurface old emotions when she already knows I’m married. For me to tell her I’m doing great and happy would only make her feel worse. And reconnecting would only remind her of what life could have been like. Hell with that. I feel she’s taking a shot in the dark maybe I’m struggling, divorced or whatever and we can reconnect. Um no. I’ll pass
Ex reaches out after 15 years?
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