Knock him/her out par hitting them on the head with something heavy, tie them down in your basement, and torture them par cutting them and stabbing them until they say they'll marry toi and stay with toi forever. If not, kill them. They don't deserve to live if they wont l’amour you.
Uhm, befriend him I guess. He must know how kind toi really are in order for him to like you. "Like" comes first before "love", even in the dictionary. :)