Someone is not respecting you for your work.
Someone else took your important project lightly. Someone else made fun of you.

All this keeps you questioning yourself.

“Am I doing things right? Do I deserve to be here? Maybe they all are right!”

When they don’t treat us right, it’s rarely because of us.
They’re themselves dealing with a lot.
Sometimes even without being aware.

Your value is a measure of what you bring to the table, your confidence and cool, and how you have the courage to figure things out when the plan has failed. 

It is rarely a function of what others do to you.

Pegging your value to how others treat you is like pegging your health to the health of others. Hardly correlated.