Love

Sounds like two ways to say the same thing, to be honest.

As Katie pointed out there are many types of love, but you cannot romantically love your dog or something. In our post-modern society, people make up all sorts of screwy bull$hit, like that having sex with 14 girls at once is legit because it all adds up to "one love," like that bisexuals are entitled to be "in love" with two people provided they're of different genders, or even that there are more than 2 genders.

If you're a guy and you're with a girl and it's gone far enough along, you're in love. If you aren't as far along, you "like" each other but not in love yet. People that argue against this basic structure are either wannabe philosophers or have some ulterior motives to argue it.

If something sounds like bull$hit it most likely is. Philosophy has been around for literally millenia, if you look back to Plato, Confucious, Aquinas, and similar great minds. I assure you that the stuff written since the 1960s is not going to have the same long-term effect as Plato and Confucious did.

To go with a cliche, you have to discover that for yourself.