I think that I do agree with that. My partner has dithered about for the last few years - trying to make up for it now, but it feels a bit late.
We had problems which knocked us, from the outside rather than between each other. Yet my partner decided to withdraw his love for a while. Which really hurt.
I think when you fall in love, at first it is giddy and passionate. After a while, as long as there is no abusiveness going on, then I think love is more of a choice, we have to decide to keep loving that person or see it crumble. We see our partners then in all their faults, but stick with them. That to me, is love.
What do you think? Do we give up too easily? Do we expect love to be because our partners make us happy all the time?