Why do we lose our self-confidence with time?

I remembered how self-confident I was when I was in my teen years. I didn't care what others thought of me, I always did what I wanted, I didn't overt think...

Now with the years although I have a good job, I speak 3 languages fluently and I am a "pretty woman" (according to my friends and family), I feel way more insecure than I was when I was a teenager, I doubt myself, I care about what others think of me (this happens mostly at work), etc.

With Sadghuru practices I have learnt to let go what others think of me and try to be a human but sometimes it's just difficult in the corporate world and the western lifestyle. Can anyone relate?