Gracie - Hi, I have only just seen your thread and felt compelled to reply.
I know this about you (and not me) just I wanted you to know that you are not alone, that you will get better and that you are a good mum.
I have had (kinda still have) PTSD, Anxiety disorder, Agoraphobia for 21 years and at its worse I felt exactly the same as you - the thoughts are linked to OCD which are undoubtedly one of the harder symptoms to deal with - along with the detached feeling (have you read up about depersonalization? - which is what they call this).
You are ill and there is NOTHING to be ashamed of - would you feel ashamed if you had any other physical illness? I would suspect not - mental illness is no different - it gets treated and you get better (or at least learn to get along with it!)
You are beating yourself up - which really wont help - you DO need to help raise your self esteem and unfortunetly only you can do this.... one small step at a time. Be kind to yourself.
I have been there - and I do understand how bleak it looks at the bottom - but there is a way up and you will get better. Your daughter needs her wonderful mum to get better.
Take care and keep talking either here or in RL
btw despite (and because of) my illness I trained to become a SW several years ago - you are not mad and you are worth fighting for.