Criticisms are free work
with whatever value you decide them to be
Criticisms can be hard to take, but here’s how I look at them.
Someone spent time and thought, even if in malicious intent, to formulate something to tell you about something you did or something you are. They did some free work for you, if you want to look at it another way.
Now, their two cents’ worth, as the expression goes in English for opinions (usually not appreciated), can be worth whatever you want it to be. You do have the final say in how you want to interpret their criticisms. Sure, it can hurt coming from someone you trust, admire, want to please, etc. However, at the end of the day, it’s up to you to decide what value, if any, those criticisms have.
Remember that, assign and appropriate value to those criticisms, and move on. That could mean forget about it, or do exactly as said, maybe more. But give it a value and move on.