I remember a time when people's opinion of me got to me a lot. What people thought of me mattered more than was healthy for me, and I would get mad and bothered when they said something bad about me.
All of that changed though as I grew up. I realized that what people say I am and what I know I am are two different things, and whether they say it or not, their opinion can never accurately define me, or change who I truly am.
Even though I am constantly changing, I still know myself more than anyone can claim to know me. It's people's opinion of who you are versus your own opinion of who you are; and which opinion is more important, and by how much, is something you decide for yourself. Both opinions are important, though I believe yours should be more. One helps you avoid useless conceit and the other enables self-actualization.
With this mindset, you can listen to negative or inaccurate opinions of you, learn from them and just move on. This is one of the most liberating changes of attitude that I've ever made. It helped me separate productive opinions from destructive ones; opinions that build a person up from those that hurt a person.