Lol, the hysteria on this site whenever a slightly off colour phrase is used is hilarious. Wait, the noice brigade will come for me hysterically shrieking because I used the words hysteria, hysterically and shrieking 😅
It's a bit of a sad phrase, bit sexist. Definitely nothing to throw yourself off a bridge over though 😆
The main problem is not the phrase, it's that it means he would not be with you if you weren't giving him sex, that sex is the only thing he likes about you - he doesn't like your sense of humour, kindness, intelligence, fun - all the things that make you you - just access to your fanny.
Long ago, I had a boyfriend I was really keen on and he was really keen on me we were happy and in that first flush of slightly too lovey dovey love - both of us. We went away on a group camping holiday with some of his friends and their girlfriends. We weren't being too much, just happy and nice to one another, holding hands the odd peck on the cheek - we kept the other stuff for when we were in private.
But one of his friends (who was in a miserable relationshipo) made a snide remark about being pussy whipped - the pretence being that this was a joke. He changed after that, he didn't want his friends to think he was - well - pussy whipped. I never forgot that comment, the look on his face, or the way things changed right after. We split up a couple of months later. I never blamed his friend for that of course - it was my boyfriend who gave in to his friend's stupid macho shite, and ruined things for himself.
So no, it's not the term, it's just a phrase, a bit sexist, outdated, nothing to see a therapist about. It's what underlies that phrase.