Issues of insecurity and identity of the human heart are something I have taken increasing interest in over time. I'm starting to think that when it comes to issues of insecurity in relationship to others, the image of a seesaw at a playground points to something worth considering.
When one side raises, the other lowers. When one side is high, the other side is low. When fear of man is high, fear of the Lord (the healthy kind) is low. When the fear of the Lord is high, fear of man is low. I've only got so much emotional care-width. I'm either getting my value from you or Him. Or when I'm super concerned about man's validation, I'm less concerned about God's. Almost in direct proportion.
And think about this one...criticism hurts to the same degree that praise helps. If you feed off people's affirmation, to the equivalent degree you'll shrink at their disapproval. It's like a seesaw. So, the less you need/want their praise, the less you'll mind their disappointment.
The answer is simple to see, but hard to activate. Disconnect your sense of identity from other people or the things you accomplish, and root it firmly in God's perspective about you. Which are final, and rather spectacular! Then, you'll be off the seesaw ride. Which is great, because those things hurt after a while. I just rode one the other day with the kids.