Stress

The common refrain is to find ways to "de-stress" or "relieve stress." Before moving forward, it's important to note that, as James Smith has touched on, stress is a reaction. Ergo, it is entirely dependent upon how we react to something. Whether or not something is a stressor is only based on whether we perceive it to be.
With that out of the way, it is also necessary to note that stress is not something to be avoided. In fact, stress should be sought out. It is how we improve, how we grow. Stress is how we inoculate ourselves from further stress of similar ilk. It is only through this stress that we can become resistant to those thoughts and feelings when placed in similar environments.
For instance; public speaking. Perhaps it is extremely stressful for you to get up in front of a group of people and speak. While there are strategies you can use to mitigate, or at least lessen, this stress, such as significant preparation of material, and practice speaking, eventually, you will have to get up and speak. Over time, as you expose yourself to this stressor, it will be come less and less stressful to you, and it will no longer cause the response within you that it once did.
We can extend this to all facets of life and realize that stress is necessary. This doesn't mean being constantly stressed out is a good idea; but rather, constantly avoiding stress is a bad one. Expose yourself to uncomfortability. And when something uncomfortable becomes comfortable, it's time to move to something else.