Truth is , we talk a lot about suffering in yoga.
(Well, that and pooping!) But do realize, the Yoga Sutras don't just give us insight into our suffering - but also, the path to happiness:
maitrī-karunā-muditopekṣāṇām sukha-dukḥa-puṇyāpuṇya-viṣayānāṃ bhāvanānātaś citta-prasādanam
Find peace and happiness through a kinship with your experiences of happiness, a compassion with pain, and indifference to negativity. // Yoga Sutra 1.33
Because even though I know, darkness is a part of living. And sometimes, snow happens. Neither has the power to steal my peace. We alone have the power to determine our own happiness.
And this alone should leave us ALL feeling very optimistic!