How to stay alive

Please help me. My cat passed away few minutes ago because of me. She want to go out of the house so I let her be because after a few minutes she'll come back again. But because of that, she was attacked by 4 large stray dogs. My cat is small compared to them, she couldn't even escape. How do you live with this guilt? How am I gonna survive? My house is full of her. Her fur is everywhere. She knocked down my mirror and yet I still keep it because of her. How do you sleep? How do you cope with this? How to literally stay alive because I think I'm closer to commiting suicide than ever. Everyone said it's not my fault but because of my actions, it happened. Please tell me how. I want to live.