Is this my fault? :(?

So my poor cat got hit by a car, she died:( I am so devastated cause I loved her so much! Not even that she was a new MOTHER! she left her newborns behind, I had no choice to give them away, for better chance of survival and care. I never let my cat go out like that and kept her so well until this one little accident. She must of sneaked out while window was open. I’m just traumatised and miss her so much. How can I get over this I just don’t know anymore I’m grieving and feel like I lost the babies and her now. I didn’t even check on her & babies that day which I feel more guilty about as I had work and thought my family at home will. I’m just gutted
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Now the lady that has my kittens ain’t giving them back! And that’s the only good memories I have of my cat!
Is this my fault? :(?
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