Okay, you are in a relationship. Being a good friend is a relationship and having sex with that friend; I can't imagine what definition you are giving "relationship" if that ain't it?

That you sound a bit desperate to not sever the relationship says, to me, that it means a great deal to you. If you "didn't care" then you both would not care if Josh was/was not more/less fond of you than you wish to believe and would not be worried. This isn't about Josh, he is in charge of taking care of himself. You either care for Josh and this relationship or you are using him. It sounds to me like you care for Josh but wish you didn't so are denying it.