i have never read a more true, more vivid description of love than this (extracted, again, from Mere Christianity by CS Lewis), and one of the most striking formulations of what it means to have a good, solid, Christian marriage. (tons better than joshua harris' book, that is true, but i sometimes think is somewhat legalistic)

p107 The idea that 'being in love' is the ONLY reason for remaining married really leaves no room for marriage as a contract or promise at all. if love is the whole thing, then the promise can add nothing; and if it adds nothing, then it should not be made.

And, of course, the promise, made when I am in love and because I am in love, to be true to the beloved as long as I live, commits me to bring true even if i cease to be in love. A promise must be about things that I can do, about actions: no one can promise to go on feeling in a certain way. He might as well promise never to have a headache or to always feel hungry. But what, it may be asked, is the use of keeping two people together if they are no longer in love? ...[There is a reason] of which I am very sure, though I find it a little hard to explain.

...

What we call 'being in love' is a glorious state, and, in several ways, good for us. It helps to make us generous and courageous, it opens our eyes not only to the beauty of the beloved but to all beauty, and it subordinates (especially at first) our merely animal sexuality; in that sense love is the great conqueror of lust.

...

Being in love is a good thing, but it is not the best thing. There are many things below it, but there are also things above it. You cannot make it the basis of a whole life. It is a noble feeling, but it is still a feeling. Now NO FEELING can be relied on to last in its full intensity, or even to last at all.

...

But ceasing to be 'in love' need not mean ceasing to love. Love in this second sense - love as distinct from 'being in love'- is not merely a feeling. it is a deep unity, maintained by the will and deliberately strengthened by habit; reinforced by (in Christian marriages) the grace which both partners ask, and receive, from God. They can have this love for each other even as those moments when they do not like each other; as you love yourself even when you do not like yourself.

...

It is on this love that the engine of marriage is run: being in love was the explosion that started it.

omg. isnt that just beautiful. in love versus love.