Cant stop want to stop

Me and Friend with benefits have been intimate with each other for the past five years. Since we’re really close friends and have known each other well over a decade it’s made everything easy. Although everything are fine between us friendship wise intimately we need to stop having sex. But for some reason we literally can not STOP.

Every time I tell him it’s over that’s it one of us folds under pressure and hits up the other as boo boo the fool I always go back. And y’all that’s when the sex is great the intimacy is at its highest. I want to stop bc obviously we can’t do this forever but atp I don’t think I know how to.

Any tips on how to stop but still remain friends?

Could this also be something deeper making it hard to stop?