I would just like to state some obvious things that perhaps you guys may have overlooked.

Modern teens spend so much time indoors, in front of screens, consuming tones of sugar. None of these things is beneficial for one's overall mental health.

Can I suggest some fresh air, sunshine, exercise, fruit and veges and water. If all of these things are lacking in your lifestyle its no wonder you are depressed.

Of course things are never so simple... your issues are genuine enough... but trust me, feeling good about life requires moving around outdoors and keeping your body well hydrated and full of nutrients.

Blessings
Cat.