Just because you have a good family, nice stuff, etc. doesn't mean that you are happy or that you SHOULD be happy. I have most of those things, but I'm not happy. But I don't dwell on all the awfulness 24/7 like you do, either. I try to find positive stuff to think about, even when I'd rather entertain dark thoughts.
I don't have tolerance for people who continually feel sorry for themselves, so you won't get sympathy from me on that point. But you WILL get empathy from me, because I've been in the pit where you are, and felt those same feelings of anger and outrage.
You're not spoiled. You just focus too much on the bad stuff in life. That's why I avoid my oldest sister like the plague. She's a constantly negative person who just sucks the positivity out of everyone, and my mental health can't handle that.
I truly believe that your depression is a MAJOR contributing cause to your negative behavior. So please go see a doctor.
Ma'am, I have Aspergers'. I'd describe it here, but truly no one would know what it's like unless they experienced it themselves. All I can say is that it makes me socially awkward and often makes me look stupid. I think VERY black and white. I want relationships but don't understand them. I sometimes don't feel fully human because I have Aspergers'. This, coupled with my loneliness and melancholy personality, makes it very easy for me to fixate on bad things. I'm not giving excuses. I'm just stating facts.
Aspergers is not something you can just get rid of or turn on and off, no matter how much you might wish to. And I don't talk to people very much about it because they don't know what it's like.
And I admit it. I'm angry at God. I'm angry that he made me this way and I'm angry he hasn't relieved my loneliness at all, even though I prayed till I was blue in the face and got out every chance I got, and I'm angry because I feel like my struggles are a big deal even though I KNOW they aren't.
But like I said, God owes me nothing. If he's the same as all of you here, I wouldn't be surprised.
What about your sister's mental health? If no one wants to be around her then she'll have no chance of getting help.