You say you are very much in love, so I think being honest will serve you well.
Communicate that your preference is to make love to him, but if he doesn’t have the drive for that right now, you understand, but you are still seeking sexual satisfaction. Let him know that you’d like to negotiate sex out of the relationship, and let him know that it will only be sex, you aren’t seeking any other type of relationship with somebody. Set the parameters, and check in with other frequently.
We don’t have to follow some puritanical idea of what a relationship should be, that very few American couples achieve, even str8 ones.