Judging sister for being in emotional childhood

My sister has been going to therapy for a decade now and I feel like she’s still just in victim mentality. She complains about her toxic work environment and how she hates it there and is bored. I found that I’m getting so tired and judgmental of hearing her complain about it. I feel like I’m being righteous because I’m thinking, “Why can’t you just learn how to manage your own thoughts and emotions and stop being a victim?!” Then I feel bad because I know I’m not being a good sister, but I’m really tired of hearing her complain about it. I know her life could be better but she’s just there. Please help me think about this situation in a different way.