Because I do and am not.
My baby has just screamed for 3 hours straight and refuses to sleep despite being exhausted. I changed her, fed her, changed her again, tried soothing her; nothing has worked.
I am exhausted. She's in her jumper right now playing quietly by herself while I contemplate jumping out the window. I have no energy and can't even talk to her I'm so upset.
She is a beautiful, bright, lovely little baby. She has so much love. I feel like she'll be better off without me. I know my Dh would have lots of family/friend support if I were to leave. He's an amazing dad. My MIL is awesome. I have an aunt and uncle who can't have children and they'd be amazing parents.
I am just not good enough for her.