Should I admit to the affair?

[hoosiermama]

I think it depends upon your motivation, and you might really have to dig deep to explore that.

These would NOT be good reasons to reveal an old affair:
Do you want to come clean in any way to cause your partner pain? As in tit-fo-tat, or revenge for old wounds?
Do you want to dump a heavy burden of guilt that you've been carrying around for lo these many years?

Only you can really decide if it would be productive and healing for your M to reveal old affairs. But don't do it to make yourself feel better, do it for the marriage if you do it.

Congratulations on making some good choices and improving your communication! The empty nest years can be wonderful (or so I hear!)