Love is simply caring deeply about the welfare of another.
The primary difference between parental, sibling, platonic, and romantic love is with romantic love there is usually a desire to be physically intimate.
Having said that when it comes to romantic love everyone has their own definition or expectations. Each person has made up their mind what love is suppose to "look like", "feel like", and how people "in love" should "act like".
Ultimately we're looking for someone to love us (the way) we want to be loved! Until that happens we won't (feel loved) no matter what is in our mate's heart.
This explains why people sometimes say to their mate:
"If you loved me you would..etc"
Essentially they're trying to get him/her to behave or love them (the way they want).