Just my thoughts, but you need to go see a doctor TODAY. I don't know if you have ever been on anti-depressants, but you should look into them. Of course, they take a few weeks to really take hold, so that doesn't help today.
TODAY, you sound like you are on the brink. Anytime you start thinking everyone would be better off without you, this sends up a red flag to me. Get into a local dr. or hospital if you can, as soon as you can.
Last December I was where you are now. My H couldn't stand to be around me, said it was OVER, period, done. (We are now living together again and trying to work it out so don't give up hope!) Anyway, I actually called him to leave work early one day b/c I felt I couldn't take care of my kids well any more. I got over that feeling w/in a few hours and told him not to come get them, so he didn't.
But I know I have spent weeks at work not doing much more than just physically showing up, and "managing" my kids more than "parenting" them, just trying to make it until I could put them to bed and be alone in my sadness...
That is just no way to live. I got help with a counselor and medication, also started running again which helped, too. You need to take care of YOU before you can be the parent and employee you want to be.
