@Shruti- I'm sorry to hear that hun.
It's the sad reality, but this happens everywhere. Not just to people who have weight issues, but for all sorts of stupid things.
I know that it hurts, and I strongly recommend letting it out sometimes. I believe in tit for tat, but then again, playing fire with fire isn't the best answer, and I love how Mahi handles it sometimes.
Just know that at some point in life, you will be teased, people will make you want to cry, and sometimes, you'll feel like life isn't worth it... but then one day, when you're looking back, you'll have the satisfaction of knowing that you were strong through something like that.