Gave moral support 20 years ago to daughter having baby in 40s/ now I wonder if that was good due to economy and other factors. How do I resolve this?

Expand Your Focus. Regrets are common, but they often come from looking at the glass as only "half empty." what about all the wonderful things about having children? Sure, you could focus only on the negatives (or assumed negatives) but you would only be making yourself feel bad, when you don't really have to. See if you can "force" yourself to look for at least one positive, every time you perceive a negative.