I'm not on FB anymore, but my missus often snoops on her ex - they were engaged for a couple of years before she & I got together. He's a bit of a prick and she likes to snoop now and then to see what he's up to.
It's close to 20 years ago, but I guess there is a morbid curiosity - she often shares stuff she's found out (they met at school and have a lot of mutual friends so it's not unusual to see them both tagged in a post).
Doesn't bother me in the slightest. It's normal to think about your past and your exes. Doesn't necessarily harm your current relationship unless you act on your curiosity.
I remember reading an article back in the late 90s that blamed
Friends Reunitedfor the divorce rate going up. I'll bet FB has had an effect on that too
