You’re not your work
As hard as it is to separate a person from their work, the truth is, you are not your work.
Whatever work or task you are given to do will always be a predefined activity with a fixed outcome. For example, the task to make a sandwich will always remain the same. How you choose to make it may differ from how another makes it, the speed to make it may vary, but the outcome always remains the same, a sandwich is made.
When it comes to you however, you keep changing, for better if you are learning and growing, or for worse if you are not. This is a fundamental difference between you and your work.
Those who spend an inordinate amount of time on their work may not have made that distinction between who they are and what they do. Their work becomes an avenue by which they seek approval of themselves from others, that is why they take work so personally. If their work is rejected, they feel their person is rejected and so they work hard, not to deliver a task, but inadvertently to be accepted.
It is worth pointing this out again, you’re not your work. Separate yourself from it and seek the right avenues to get reinforcement for a better self concept.