It reminds me of that Chris Rock quote from Everybody Hates Chris where he said “Even when a woman isn’t doing it with you/don’t want you, they always care about who you’re doing it with”
Its because they like to juxtapose themselves alongside that female you’re dealing with and determine if they’re better than them or not, women are always in competition with each other even over dudes they don’t want. It’s why as soon as you’re taken women start showing up. And also like you said that is free validation going out the window for them.
Crabs in a barrel shyt. If You a man that leveled up in every aspect of your existence, those same women will hate you. At this point, call them Devil worshippers and KIM.