I was talking to my gf about this the other day via email... I can't be bothered writing it out again, so ill just copy and paste. Sorry if it seems out of context:

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The mechanics of it are like this: there are a lot of kinds of love, but two main kinds. I would call the first kind worldly love. It is like the typical love you would think of between a man and a woman. even though its called worldly love it isn't a bad love. The other kind of love is "base" love... The kind of love a mother would have for her child, or that God if he existed would have for the universe. There is nothing you can do to change it, and it is completely unconditional and totally accepting, compassionate and forgiving.

In a relationship, I think "true love" is a combination of both of these loves. Worldly love is weak and conditional, so relationships based on it are not strong. The perfect relationship has the unconditional, infinite, compassionate love as the base, and then on top of it sits the worldly love which makes the people involved closer. Since the base love can be had for anything, even a rock or a murderer, the thing that makes a true love special is the combination of worldly and base love. A successful relationship draws on both to succeed over a long term, for example... Say a married couple has "true" love, and at 60 years old the man is no longer physically attracted to the woman. The hole made by a lack of physical attraction is filled by the unlimited base love, which takes its place. In this way, the man can remain completely happy with his wife, despite not being physically attracted to her.
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So yeah. That's my opinion on true love in couples. If you want to get technical, I would consider the "base" love that I described to be true love.

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