I did bump in to the OW once. I knew her because she had searched me out on fb and messaged me. Although my instinct had been to correct the spelling mistakes in her message and send it back, I let dignity win and ignored it. It had her photo on it though...
Anyway, fast forward a few months and I pop in to a diy store in my lunch hour. I'm in my work clothes, think boots, pencil skirt, fitted jacket, makeup. I see her. She's in badly fitting jeans, roots showing in hair and - best of all - she's about 4 times my size. I very pleasantly say " Excuse me, but are you ....?". She agrees before realising who I am. I nicely tell her that she is very welcome to exdp, that there really is no need to worry as I won't be inviting him back but suggest that she doesn't give him any money as he had proved to be very untrustworthy in that area.
She is mortified, apologises for email claiming to have been "drunk" ('how classy', I think) and then starts apologising for looking such a mess. We walk out of shop together in rather surreal manner to find we are parked next to each other. She opens boot of her old, dirty car. I climb carefully in to my sports car (which, thank you god, I had cleaned the weekend before).
I drive off, having received an apology and been complimented on my appearance. I go back to work and tell EVERYONE I can think of. At least twice.
Ok, maybe I could have kept it to myself in manner of mature, generous-spirited adult, but it just felt too gooooooood!