“If you take a handful of salt and pour it into a small bowl of water, the water in the bowl will be too salty to drink. But if you pour the same amount of salt into a large river, people will still be able to drink the river's water.

If your heart is small, one unjust word or act will make you suffer. But if your heart is large, if you have understanding and compassion, that word or deed will not have the power to make you suffer.”

Thich Nhat Hanh

When you first approach Buddhism, there is the clear message of hope found in the Four Noble Truths --

yes, there is suffering in life, and
there is a known cause of it, but
it is possible to end it, and
there is a path to follow free yourself from it.

From the Second Noble Truth we learn that the principal cause of suffering is "clinging" to things in life - almost anything - objects, people, thoughts and beliefs. Letting go then means learning to loosen our grip on all those things we are holding so dearly.

The primary way we can loosen or let go of our clinging is by willingly and courageously investigating all the ways we actually do cling and see how they serve a liberated and peaceful life or not. Just pausing with words like desire, attachment, striving, wanting, craving, grasping, searching, and needing can start to illuminate the pretty vast world where clinging often occurs.

It's also important to understand that clinging is in direct opposition to the impermanent reality of existence -- nothing lasts forever, everything is always changing, and every moment is new and different than the last. Yet, we get stuck in hoping things won't change and try to control the ever changing landscape of life. So, we suffer.