A relationship should never be used as a means to have sex. That will only hurt people.

Honestly, to me it sounds like you don't really want a (romantic) relationship in the first place. And that's completely fine. Don't try to force something on yourself that you don't want. That will only hurt your partner and disappoint you. It's completely fine to just want friends with benefits or one night stands (or both, as long as you're careful). You do you.