How to get over the fear of bullying?

When I was a kid growing up, I was pretty consistently bullied even when I changed schools even now in college it still happens but in a lesser way. Overtime I have grown quite tired of constantly being bullied and no longer have a tolerance of it, I easily break down if there's even a bit of bullying. I have become very sensitive to it instead of being resistant I think it's because of the trauma of it. How do I fix this?