Most days, I would feel like I could only come on here and vent similar frustrations! But today is a pretty good day, so I'll try to add some of the things that work for me.
Sometimes the problems are real and must be dealt with (sick or hurt, need to get out the door to pick a child up from school, baby needs to nurse, etc.) but often the problem is really only a mental one (the house is messy, I think the kids need a bath before bed, etc.). If I am in a bad mood, I try to catch myself and ask - Does this have to happen right now? Or can it slide until tomorrow?
Now this thread says "support" in the title, so no flames allowed! Often what causes me frustration is trying to live up to the NFL ideals of MDC. So if I am in one of those moods, I have determined that our family does better if I forget the "ideals" and just let the kids do what they want (even if it is watch TV or play computer games) while I nuke a bowl of Beef-a-roni for their lunch. Now I know someone else will post that their family gets in a better mood by all joining together to chop fresh vegetables while singing songs, but I haven't found that to work in my own family.
When I am about to snap I have told everyone to go get in the van and we just go for a ride, usually to get icecream or treats from a drive-thru. I have told the kids that once they get in the tub they can have freezer pops. I have told the boys that they can stay up as late as the want, as long as they stay in their rooms and I can't hear them. Is this as good as healthy foods and a good nights sleep? No, but on those days when perfect parenting seems as far away as the moon, it seems a better alternative than the yelling and screaming that I am trying to limit.
On our better days, the bedtime routine works best if I can stagger things. One child bathes before dinner, the other bathes after dinner while I am doing the read books/brush teeth/neaten room routine with his brother. DD either comes last if she took a nap, or else she got her bath and pajamas in the late afternoon once it was sure she wasn't going to nap, and would be going to sleep earlier. I try to keep the kids somewhat separated so that they can't antagonize each or, or in the alternative, get playing together so they don't want to go to bed. Doing the kids one by one may take longer than trying to do the bedtime routine together, but it doesn't seem longer since it is much less stressful for me.
I always have a book on tape (or my iPod) to listen to. That also helps distract me from the frustrations I feel with a messy house and wild kids. My DH laughs at me, but it really helps keep me sane.
And the before dinner wine - add some cheese and crackers and its downright civilized!