I saw an interesting tiktok re a new Facebook group called "Are We Dating The Same Guy?" for women in NYC.
EDIT: Apparently the original tiktok I linked to was deleted (reported by angry men, lol?), so here's another one: https://www.tiktok.com/t/ZTdcmAqdq/?k=1
FB has never been a platform I've found worth all the crap that gets posted there, but if I was actively dating and in NYC, I would be joining this group in a heartbeat. There are similar groups for other cities, so definitely do a search if you want to see if a group exists for your area.
Cosmo article about similar "Are We Sharing Boyfriends" groups: