Quoting Gir!:" I have a 4 yr old and a 1 yr old.. With everything going on in the last year I've just shut down for ... [snip!] ... the point where I yell at him and just don't get up or I ignore them when they start up. I feel so mean and bitter all the time"
If you can, try getting a break from them. My Mom came and visited a few weeks ago and I was just so worn out from DD's attitude lately that one morning she just took her down to the beach and let me nap for a few hours. It made me feel 1000x more refreshed and made the rest of the weekend a lot more enjoyable. I feel for you on the screaming like a banshee, DD does it any time she doesn't get her way. Drives me nuts -.-