How do you deal with being the worst parent in the world?

IN another post, I asked how to stop feeling angry and I admitted to breaking my kids teacup out of anger because she had soaked her entire bedroom floor. I realize that isn't right, I realize that is bad, I realize I am a scum of the earth piece of **** parent. A poster called me abusive and said I should get my tubes tied. You know I am not perfect, I am sure if were to closely examine her life under a microscope she would have some really shameful crap she wouldn't want to admit to. I did admit to it and I asked how to stop feeling angry enough to act that way. Now I really just feel like a worthless horrible human being that should kill herself and ,make the world a better place. Really what is the point if I can't be perfect and make little sandwiches and let my kids douse the entire house with kool-aid? I feel like giving up totally - I will never ever be Mary Poppins. I was abused as a kid, my father would leave holes in the wall, shaped like me. I promised myself I wouldn't be like him. I am not violent, what I did was completely out of character. I am sick of being on welfare, I am sick of being a full time student who has no time to study, I am sick of my husband refusing to work more that 1/2 time at night and watching tv all day. I am sick of being the only one with any ambition. I feel like I am failing in all aspects of my life - especially as a mother. Does anyone else ever feel like a POS after someone answers that way?