I want to be your love - If he is your love, he is your boyfriend or spouse. I want to be your loving- Loving is not a noun. You could say "I am your loving boyfriend, or loving husband/wife. It is an adjective. I want to be your lover - Lover is your romantic husband, boyfriend/girlfriend, etc.

I want to be your love[ noun] = I want to be your boy/girlfriend I want to be your loving incorrect- here' loving' is a verb. Correct: I wish that I was loving you I want to be your lover [noun] = I want to be the person who sleeps with you

This is the difference - Yo quiero ser tu amor - Yo quiero ser tu amado - Yo quiero ser tu amante

love : amor... loving : amoroso... lover : amante