It means he really likes you or accepts you as a friend
OK, Jacob does not actually love Renesmee. Imprinting and love at first sight are not at all the same. When he was planning on killing her, he hadn't seen her face yet. Once he saw her face, he imprinted and he describes the feeling as "gravity wasn't holding me to the earth now. She was" (this is not word for word). When a wolf imprints, all he wants is to make the object of his imprinting happy. So Jacob does not love Renesmee, he just can't leave her side or else it causes him pain. (note: this answer came from a person who does not like Jacob at all. I am simply stating what is said in the books.)