Ya I keep in touch but by that I mean, every once in several years, I'll drop em a msg and see what's up. I have high success rate of banging them again, because I never do drama first of all, and when I leave, it's always in good terms, then I also apply no contact rules if there was more emotions involved.
Here's an example; I was banging this chick 8 years ago, but she wanted a bf so we split. Then she was with my best bud which was a 6months nightmare from my understanding, then she met some guy that she married. I sent her a msg 2-3 months ago to catch up, she's fckin sick and tired of her husband and marriage, then I explained her how monogamy doesn't work and she's a walking proof of it. Then we banged.
She knows I have a gf, she likes that I am discreet and I made her understand it doesn't mean that she doesn't love her husband anymore, it's just that homo sapiens aren't meant to be monogamous.
Everyone is happy in the end, she's feeling satisfied and the guilt is tolerable. She's a very smart women with degree in bio genetic I think?
I am in good terms with a lot of my exs too... We'll get in touch when they get sick of their beta bf or in between them sometimes. We'll bang until she finds another beta... some of them just don't get it tho.