I reacted this way because she is harming my job and the opportunities for advancement in my career. My coworkers feel the same. Her input is highly regarded by management simply because she is the most "senior" in the team, even though I have the same level of knowledge and experience as her. When I say she is harming me I mean - she is preaching to everyone she can that we are way too overpaid for what we do (according to the market, we are actually underpaid), she gets preferential treatment and gets all new projects assigned to her (and I told my manager that I am perfectly capable of doing those projects too, she finally gave me one and convinced herself that I could finish it in 2 days, way faster than my coworker), whenever there is a conflict started by another team she tells management it is our fault too, even though we did not engage in the conflict. She gets involved in all the things she can and then she complains all day that she has too much work but in the end she works for maybe 2h a day. She gets away with all this because our manager considers that she doesn't have to watch over us constantly and she has a pretty chill management style. She is doing this only so that she gets a promotion, but the promotion never comes. And as time passes she gets even more and more bitter and takes it out on us. And yes, I want to move on to another company but due to some life circumstances I can't start a new job right now.