<human>: Can you condense the text into a few key points?

My sister is severely depressed and tonight is the first night I realized the extent for it. Now my sister and I have always had a rocky relationship, and I am inclined to believe that it started when my sister ratted me out for smoking bud back in 9th grade.

She has been "sick" for a good 2-3 years of her life. I use airquotes because im always at a disbelief towards that matter. Due to lack of diagnostics when she was sick and I believe she was faking to get out of commitments. Now I know I sound like an asshole when I say that, but I just have always felt that way.

Now we hardly talk, and when we do its never more then two sentences. During the time she was sick she stayed at home and missed so much school for 9th 10th she has to take summer classes to make up. She is very ignorant to stuff, and lives in her own little world that is her room, her youtube makeup videos, and her tv. During these few years she put on alot of weight.

 I feel like this weight is the root of her depression and that she does not have many friends, and tonight she freaked out in such a way I was freaked out. She was yelling and cussing at the top of her lungs and I just watched her horrified. She looked at her worst, rock bottom. She takes anti depressants and dropped her dosage to get off them, and you can tell she is alot less happy. I wish there was something I could do to help her fix herself. I have had problems in my past, and deal with anxiety and temp. depression but I have never felt it for an extended amount of time. Im very worried, what do I do to help her and fix our relation ship?
<bot>: Depressed immature sister is at rock bottom, and our relationship is awful. I'm legitimately worried and sad for her, what can I do to help?