The ancient Greeks had different words for different flavors of love; spiritual, romantic, friendship, and I imagine one could separate it into a more varied spectrum. In English it seems like we get by on context for the most part, and often skip the bits we don’t know how to handle. I’ve mostly seen “I love you” traded either between people in romantic relationships, or family members, for which there is usually a fairly clear divide.
But language custom seems to fall short in my experience for expressing love to other people. There’s perhaps a little bit less of a social friction between women friends. Guy friends usually have to toughen things by changing “I love you” to “love ya” and appending “man” or “bro” and adding a tone of faux mockery.
I haven’t really encountered the use of the general or spiritual sense, as in love for one’s fellow people. Maybe they say it in churches. And I haven’t seen a way of expressing the changing sense of the word love for friendships that grow into dating and then deepen into further stages.
I suppose most people don’t bother thinking about it too much, but maybe you or someone you know has found a creative solution for expressing the nuances of a word that covers such a large and potentially progressing range of human experience.
I’m more in the strong and silent camp. I tell my wife and kids I love them because I know it’s important that they hear it as much as through my actions. With my guy friends, expressions of affection have never been needed or wanted. We’re friends and we’ve been friends for more years than I care to count. We talk about important (life) things when warranted and we talk about bullshit things when we just want to catch up on things less important. Because we live far apart, there may be weeks that go by when we haven’t caught up on the phone. When we finally do talk, it’s like no time has passed. In short, nothing says “I love you, man” than just being there for each other. The love is implied.
Now, I’ve got two kids in high school. I noticed the guys now a day will do that faux mockery stuff you mention. It’s all, “Hey John, that shirt really sets off the blue in your eyes - I love you!” or, “Steve, those calves are looking fine today - love ya!” It’s all in jest and a bit precious but I guess they’ve embraced the bro-mance trend but mostly I think it’s just teen clownery. They’ll grow out of it.
As for me, I think it’s probably my turn to pick up the phone and call my best friend. There’s a bunch of new 2014’s coming on the dealer lots that we need to catch up on.