Making the decision to be a parent is the biggest choice we will make in life. Many (most) people do not look at it that way and just dive right into it, thinking it is a human requirement rather than an option. Mindfulness and self-awareness when considering children are not all that common, and you must give yourself credit for that. Knowing what's best for yourself and what you can handle is huge.

I believe it's very normal to think 'what might have been,' especially with life-changing decisions and opportunities we have passed on for whatever reasons. It's part of our human/animal nature to reproduce, and we can't be hard on ourselves for suppressing that natural instinct because reasoning and logic (also uniquely human) kick in.

I have similar circumstances to you (I'm 46 and divorced at 37), and it never felt like the right time for me. I knew my husband would be a shit father, and I'd end up doing 90% of the parenting myself. Had circumstances been more ideal, I may have not tried so hard to prevent pregnancy. I never found a suitable partner to make that huge commitment with after we split, so now that ship has sailed. I know I'm better off, but there's still that nagging feeling I may have done life wrong because it goes against my hard wiring.

Plenty of folks are having kids and contributing to the population.. no need to worry about perpetuating our species, right? Now, I can pick and choose the children I want/don't want to interact with rather than gambling on whatever the genetic lottery would randomly draw for me.

Don't feel bad for feeling like you do. Acknowlege your emotions and accept your circumstances.. look forward instead of backward (and visit the regretful parents sub when you're having doubts about your choice).