What is LOVE

It's Valentine's Day. A day full of love—whatever that is. I don't think there's any one, uniquely right definition of “Love.” People probably vary widely in how they approach the concept. Far be it from me to tell anyone they're going about it wrong. I think it's one of life's big mysteries, to figure out how we're going to confront the concept. In that regard, it's perhaps more a question than an answer. What I offer here is my own answer, not any Grand Unified Plan for Love you are obliged to subscribe to, just a written record of how I personally approach the matter.
A question that often fascinates me is “Why do you love me?” It's interesting because it seems to presuppose a certain kind of answer. “I love you because you're a good cook.” Or perhaps, “I love you because you're beautiful.” Or maybe, “I love you because you're such a good singer.” Personally, I find this a dangerous way of approaching the concept. If one defines love in terms of a service provided or a characteristic that may be transient, it might be that if circumstances change, there will be no love. In fact, I wouldn't be surprised if some people do define love this way. Some might say such love is shallow—I don't know, that's perhaps a value judgment. I'd like to steer clear of that. But I will say it sounds fragile, waiting to be broken by an arbitrary change in circumstance.
Some people appear to perceive love as simply a more intense version of like. “I like you. I like you a lot. OK, it's so much I guess I love you.” This too seems fragile, but more than that, I think it doesn't create a space for the commonly observed place where we can sometimes find ourselves loving someone we do not like. Certainly that's not well-explained by simply saying that love means intense liking. So I don't use the word to mean a kind of intense liking.
In fact, I think the part where one can love someone they aren't liking gets closer to the point. It takes commitment to have that kind of feeling that allows love to span the rough times. Whatever love is, it had better somehow explain this whole business of commitment.
I think of liking something as a sensation of positive feeling, disliking as a negative feeling. But love is more like a decision. It's a switch I can decide to flip. I can choose to love. The decision may be for an arbitrary reason. Maybe I liked your smile in that moment. It could be I think you're a great cook. Or perhaps we just shared an amazing experience, like climbing a mountain or building a house together.
I guess what I'm saying is that the reason one falls in love doesn't have to be the reason one continues to love. If we climbed a mountain, we don't have to always climb mountains. If we do, that love is fragile. Or so I claim.
To my mind, the liking of something expresses a positive sensation that can be more or less strong. But the loving of something is just there, or not, or at least it is to me. It's notable for its constancy. I make the decision to love, and after that there's no more work to do. I just love. That's the commitment part. It's a decision that the love will be there regardless.
This formulation neatly gets around the thing some people have where they pester you every moment of the day to find out if they are still loved. Love is not supposed to be that changeable. I don't have a problem about expressing that I love, but I do feel the expression should be pro forma. The person should just know and rely on it. What other point is there to it? If I can love you at 2pm, not love you at 3pm, and love you again at 4pm, then what is it I committed to? It needs to be more durable, not to mention more relaxed. It needs to reinforce the other things I do for you, especially things that require effort, not call into question the validity of doing those things.