Im cracking up pls help?

i feel totaly out of control i go from being fine to a complete and uncontrollable rage to floods of tears to depession and suicidol thoughts. i just cant seem to cope with anything anymore nomatter how hard i try. i finnish everyday telling myself that i will put the kids in care because i love them so much i dont want them around this, they deserve so much more then me, but then cant bring myself to do it because i couldn't bare the thought of them not being here with me, is that selfish i just want whats best for them and i dont think im it. im failing at every turn and i cant see a way out.