We all are human and snap. I *try* to do Love and Logic, too. I think I need a refresher course. I'm sure it would help me be more aware and conscious of my reactions. At any rate, here are some tips that help me (I need to apply some of them to my own life right now. This morning was full of whining, slow-to-get-ready kids and a yelling mom).
EXERCISE!! My kids know that "Mommy goes to exercise so she can be nice." I don't necessarily enjoy running, but I love how I feel afterwards. And there are plenty of classes at the gym that I genuinely enjoy that clear my mind, push my body, make me feel like a winner, and just leave me on a post-exercise high. If nothing else, it gives me a break from the kids when I need it. I'm too busy to do this all the time, but when I'm really frazzled I'll do the hot tub at the gym after exercising. Once I went and just put the kids in the daycare and read a book in the locker room :) It was just one of those mornings (and I pay for the daycare there, so I don't feel bad using it for what I need).
Turn on some music that you love that just gets you in an awesome mood and dance or clean or relax to it (I have some nice noise-cancelling earphones for when the kids are screaming or whining too much). I should do this more often, because I felt so elevated the few times I've cranked up my music.
Take a break every once in a while, trade with a friend, have your husband watch them while you have a day or night off with friends, or get a sitter if you have the money. And spend it doing something that fills you up and with positive people you love. I don't do this as much as needed because I feel like I'm too busy to take time away, but you've got to be full before you can fill those other little cups up that depend on you.
Get enough sleep. I'm meaner and cope less and I'm grumpy when I'm tired (which I feel like is every stinkin' day! I need to take care of myself and get more sleep, dangit!) And make sure the kids get enough sleep so they are better behaved.
Look at their behavior -- are they just being demanding kids, or maybe there is a legitimate need that is being unmet. Some one-on-one time with each of them where you give them attention and love will go a long ways to boosting relationships and moods and behavior.
When I'm really resenting one of my kids or having a hard time being around them (sometimes they go through phases that are really difficult) I look at pictures and videos of them when they were little. It totally softens my heart towards them and helps me remember all the warmth I have ever felt towards them. It also helps me see how fast they grow up and reminds me to enjoy them here and now while they are mine and living with me. I'll miss this someday, the good and the bad, and this helps me remember that. We'll cuddle together and flip through a scrapbook or watch a family video and we're bonded and feel more loving towards each other.
We're all there with you and wishing you the best! I have a cousin whose mom was a stay-at-home mom, and she just remembers feeling like her mom was unhappy and resentful and frazzled. I'm sure her mom was just trying her best, but that made me sad because sometimes I worry that's what my kids will remember in their childhood. I try to tell them (and really mean it) how lucky I am to stay home and play with and teach them and express that gratitude to my husband for making it possible. Gratitude does wonders for how you feel inside, so maybe write or take mental note of the beautiful things in your life on a regular basis. I've recently had a friend lose a child and boy does that put things into perspective. Guilt and scarcity mentality and fear of losing a child aren't productive feelings, but it has been good to change my heart from focusing on the negative to being grateful for the negative. I want both the good and the bad of my kids, because when it comes down to it I'm just so happy to have them.