Don't question the worth of a moment based on your perception alone. Don't question the usefulness of beauty because you can't see or recognize it. Don't doubt the amazingness of the life you're living without knowing what other lives you've touched and in what ways.
Nothing is permanent, and everything that is happening now must be enjoyed, dealt with, lived in... now. Because there's another moment right behind it that must be treated the same way. Are you prepared to miss it because you're still in some awful past moment? And if so, why hang onto such a thing, considering everything you could be experiencing in the present?
Not all of life is great, but one minute alone with my child on a dark trail was enough to remind me that no number of bad days will outweigh the beauty that surrounds me in every moment of every day. Stop and pay attention. I have missed too much already. What about you?