Awe, sweetie, wish I could hug you, seeing that I can't, here's a cyber hug.
Get your mind off of it. Do a fun hobby- do you like to paint? Draw? Do puzzles? photography? crafts? Do something enjoyable to take your mind off the stress of losing weight.
I know how hard it is to have family on your case at every turn- they did it to me when I was growing up. My Mom and brother were always on my case, and it hurt. Every time i see my elderly aunt, who has alzheimers, she gets on my case for my weight loss (funny, she forgets a lot of things, but not how heavy I've been most of my life!).
You're doing this for YOU. Not anyone else. Read all over this board on great weight loss tips. Put together a plan of action that is comfortable for you to do. See my You Tube post on this board- something I am sure you'll enjoy, being young. Get up and move- dance to your favorite music or walk/jog to it. Nothing makes you feel better than exercise, as it releases feel good chemicals to your brain and it reduces stress (this is the truth, it really does work!).
Start tracking your calories, but be smart about it- don't go down too low just to try to lose too fast- that's not healthy and sets you up for a lifetime of binging and will mess with your metabolism. Find the correct calorie amount you need to start losing in a healthy manner. Lots of veggies and fruits, 2-3 proteins a day (one serving of meat protein is the equivalent to a deck of cards). On a nine inch dinner plate, at least half should be filled with veggies, one portion protein, one portion starch (rice, pasta, dinner roll- small portion, of course).
Hang in there. We're all here for you, ok?

Just keep posting here- no one will judge you here, and we'll all give you the encouragement you need to succeed on your weight loss journey!