How to stop getting depressed over mean things I read online?

[lola]

I do my best to avoid social media (for ex deleted my facebook and twitter), but sometimes comments/views of people will be unavoidable. I saw mean comments about a celebrity I'm similar lookswise to, and saw the most horrible comments about her appearance. Even then when I see horrible comments about anyone it makes me very upset. I try to not let it affect me but I can't help it. It really does hurt. I spend a lot of time away from the internet but sometimes have to use it for school etc. I just cannot take criticism. Even though I get a lot of compliments, the few mean comments from bullies are the ones that consistently play in my mind. I concentrate on those comments and it makes me feel very depressed, upset and like I don't want to live. I know not everyone will like you in life but it hurts me deeply. Please help. (I'm 17 btw)
I mean, celebrities I think are gorgeous get called by many people online as unattractive and it hurts me because I feel as if, if they consider those gorgeous celebrities as unattractive then I must be awful. I know it's pathetic, sorry.