The perfect storm

I am having all sorts of acting out issues with my daughter. I suspect most of it is just sheer jealousy or her twin brothers. We did great for the first year, some jealousy but nothing out of the ordinary. Sofia has always been an alpha. Put her in a social setting with her peers, she typically has a dominant personality and temperament - first in line to do whatever is required, pretty good at listening to the teacher. Since the boys started walking, it's like all the negative aspects of her alpha personality have intensified 100 times. It's exhausting, disheartening, hurtful, depressing and exhausting, to name a few emotions.

When the boys are not around (napping or asleep) she is your average 3 year old (with a bossy streak). There are moments of frustration for her and us, but overall, she's engaging, fun and sometimes even delightful. When the boys are in the mix, she turns into a spiteful, mean spirited little bully. I realize the strength of those words, but honestly, that is how drastic the difference is. She hits, yells, pushes, doesn't listen, acts out, etc. I realize that all of this is attention-seeking behavior and part of her job as a 3 y.o, but I can't help but think her age, the boys' burgeoning independence and her temperament have created the perfect storm. My problem is how to minimize it. She gets so much attention as it is; I feel that the boys get the raw deal. I am torn between being there to nurture them and spending time coaching her through her emotions. There don't seem to be any easy answers.

I realize that my situation is not the normal sibling relationship, so it makes it hard for most of the parenting books to address the situation and offer specific strategies on how to handle it. I've read so many and I "get" what all of them are saying. It's just incredibly hard to follow through with so much of it due to the mere fact that my husband and I are outnumbered.

I try to make "special" time for my daughter, always, because I so value our Mommy/daughter time. I grew up without a mother, so I don't have a guidebook and only want to make sure she is raised in the most emotionally healthy way (unlike my own upbringing). When I'm at my lowest, I am actually resentful that she doesn't appreciate all that I do for her. I hate even admitting that.

I picked up a few books - Siblings without Rivalry and Toddler 411, so plan on doing some reading. Not sure if it will help but I just feel so out of control and desperately seeking feasible, tested strategies for dealing with this type of situation.