Suffering

We were taught in priesthood/relief society a week or two ago from the Joseph Smith manual that suffering prepares us for the celestial kingdom. I got to thinking, if heaven is a place of peace, rest, and happiness, how would experiencing suffering and pain prepare me for that? I had two thoughts on it -
1. Suffering keeps us humble. It teaches/reminds us that we need God and each other to get through this life, that we can't make it home on our own steam.
2. It's part of the opposition of all things. The suffering we experience, and see others go through, shows us how precious life is, how rare true happiness is, and how great and plentiful our blessings really are. I mean, how often do I thank God for my health? Usually right after I get over a cold or flu or something, but then it slips my mind until I get sick again. Or for my home, or a fully functioning body, or even my family? I hate to say it, but it's probably my suffering that keeps me on the straight and narrow.

I hope someday to get to the point where I'll just stay on the path back home, without having to be dragged back on track kicking and screaming.