Feeling angry about my sisters depression.

[hersecret13]

I have been suffering with depression for my whole life, and so has my sister. But for some reason she gets to let it affect everyone around her, act like a total bitch, ice everyone out and treat everyone like shit..
I understand better than most the affects of depression. but I dont understand why I wasnt allowed to be that way, and she does. She gets to treat everyone like shit- say reckless stuff about herself all the time. Deny ANY help.. It feels irritating as someone who also struggles with depression. I want to die too - but I dont make it everyones problem.
I try hard to maintain a relationship with her, I try conversation, small talk, asking if shes oka - but all she does is either ignore me.. ice me out.. etc.
Why is she like this?? why does she get to be this way - but if anyone else is like this she makes it their problem.
I just want her to be a good sister to me, all she does is treat me like im a burden to her, like just because were in the same home, she must tolerate me. It hurts because she told me id never be the sister I wanted.
But shes perfectly capable of being that person to her friends.
Depression isnt an excuse to be a fucking asshole.