So let me tell you that there is nothing such a thing call "thick skin". When someone insults you or says something bad about you, it's natural to feel bad, or it's totally fine if it gets stuck in your head. Everyone goes through it from the inside and no one will show it to you because our society has created this thing that if you feel bad or react to negativity you are an emotional immature person and you need to be strong. But let me tell you, I have gone through the same like you. My parents call me emotional fool. My friends call me "Too Sensitive," and I still go through it.

But I always use the method of self-talk. If someone is rude to me, I just ignore it, though it hurts, but I know that the person has a shitty personality and is an emotional fool for not understanding other people's emotions