Probably everyone here has heard of Venus Cuckoldress. She has a rather robust social media presence. She has now started a service that does matchmaking services for cuckolds and cuckoldresses. It's not a typical sign-up and participate in a forum kind of thing, but if you're serious about trying to find someone to share a cuckold relationship with, this might be something you want to try.
Cuckold Dating and Matchmaking - Welcome to Venus Connections
Venus Connections is a matchmaking service for single women and men who want a loving cuckolding relationship.
venusconnections.com