How to deal with a family members attempted suicide?

Okay I'm 14. I have a younger sister who's 10. Last night my dad and I were watching her end year dance concert. When we came home, we found a suicide note, written by mum, and telling us it was out fault and that she was leaving. My poor little sister went into her room and found my stupid mother on the ground, apparently dead, surrounded by pills and burning candles. I called an ambulance, and she was taken to hospital, only to return later that night. We were taken to stay with my auntie. My mum has never properly liked me, but this, in my opinion, has taken it too far. I can't even begin to register the anger inside me after this. Her telling me and my sister it was out fault was one of the worst things. My poor little 10 year old sister, walks into a bedroom to find what looks like a dead mother. Right now, I know I should be kind, sympathetic, but I'm just disgusted. My and my sister keep waking up crying from nightmares now, and I don't know what to do What do I do? Please?