Is it normal to be mad at someone for pointing out your insecurities?

I kind of feel like your parents may have let you down by not building your confidence. They should have showered you with affection and taught you to be proud of your self and love your self. Everyone has insecurities and flaws. We are human. We also all have our own opinions about things and people. You just need to make sure that your opinion of your self is always high and own everything you do. Confidence and honesty to your self can help you to overlook other twats opinions. Who gives a fuck what other people think when your opinion is the only real one that matters?

Maybe don't think of it as people validating you. No one likes to be told about their insecurities and flaws. However, it's life and it's up to you as to how you react and deal with the information. I, personally, feel the best thing to do is rake it a constructive criticism, learn from it and try some changes or build on it - become a better you. Try and talk to people, get perspectives, don't sweat it. There's good and bad in everyone, just make the bad better :c)

I think self-validation and affirmation is more important than trying to convince other people.

Forget what other people think of you, know your own worth. As long as you know you're making steps to better your situation and make things as good as possible for yourself, it's easy to find self-worth. Also it's important to acknowledge that you're human and not perfect. If you are fully aware (but still thinking positively) about things you can improve about yourself, nobody can upset you by pointing it out, because you already know and it's not a shock to you.

In the long term, that will make other people respect you more as well, when they can see you have confidence and self-assurance. People naturally flock to individuals with those qualities.

I feel you...I've had the same problem since I was a toddler too. But I've found people (few friends) who understand me and love me the way I am; I'm sure you will do too, in the meantime you can distract yourself with other things. And remember, you're a wonderful person and don't need to prove anything to anyone.