@Foofie,
I'm not a big believer in unconditional love either. That's just an ideal. No matter how much you love someone, there are always things they can do that can kill that love.
People who manage to stay together for a lifetime do so because, in addition to basic compatability, they have cultivated values like patience, tolerance, commitment, and forgiveness...not some overly-romantic concept of "unconditional love."
Real love is hard.