I've experienced times in my life, as I'm sure you have, when I was experiencing heartache or grief and I just didn't feel close enough to anybody to tell him or her about it. Such times can make a person feel isolated even though he's surrounded by people. Yesterday, I read a couple of verses in the book of Proverbs that do a great job of explaining the depths of private grief. I often wonder if God doesn't orchestrate such times so that we'll seek him for healing instead of others.
Proverb 14:10 says, "The heart knows its own bitterness, and no stranger shares its joy." In reality, no person can ever truly taste our bitterness or experience our joy to the degree we can. Ideally, a spouse or a best friend, can and often will hurt with us, but neither is present in the heart to really know the depths of such emotions.
Proverb 14:13 says, "Even in laughter the heart may ache, and the end of joy may be grief." Some people use laughter as a mask for pain. I'm not one of those people. I'm sort of known for having a steely demeanor and I've never been thrilled about that because showing little emotion often makes people believe that emotion isn't present. That's a post for another day.
But does God really use all of this private grief? I like what C.S. Lewis said about this in his book, A Grief Observed (a book created from his journal after his wife died): "But suppose that what you are up against is a surgeon whose intentions are wholly good. The kinder and more conscientious he is, the more inexorably he will go on cutting. If he yielded to your entreaties, if he stopped before the operation was complete, all the pain up to that point would have been useless."