The best revenge is success.

There are people who belittle you because of somehow your current state and the achievements you had achieved ,but for them it is not an achievement at all. But instead of fighting with words that soon you'll going to regret, why not take the anger as a motivation. Mold yourself to be the better version and achieve more to gain the success in life. You'll see that one day, those who look down on you will envy your life as a successful one. Don't rush things as everything has its on time. Have a smile on your heart.