Demi-lover

A person that a demisexual enjoys their presence or be attracted to some of their qualities without having an interest in dating them or building a romantic relationship with them.

Fine, you want a word for our relationship. You are my demi-lover. You know, I can't love you but for you know I will be there for you the day you feel down and I will be happy the day you find somebody better than me. However, until then, let me be with you, let me kiss you, let me hold your hands.