Take absolutely nothing personally. Including your thoughts your beliefs, the behaviour of others. Life. I mean this in all seriousness.
Beliefs change. Behaviours change (Also, you have no idea what’s going on in someone’s mind, and people behave in a certain way because of you, they behave in accordance with their own beliefs). It’s all ego. Your ego is not you.
The next time “you” tell “yourself”,” I am too fragile, my skin is too thin”, ask yourself, “Who is saying this?” Observe your thoughts and beliefs and behaviours. They are not you.
Observing yourself (instead of judging beliefs and beating yourself up) will help you realize that absolutely nothing needs to be taken personally, and the idea of needing to have a thick skin will be kind of nonsensical.
If you need help wrapping your head around all this, do read There Is Nothing Wrong With You by Cheri Huber.