Hi, I’ve been working at my company and worked hard and got a promotion to be a team leader taking care of 30 employees. There is a power struggle and bullying (making fun and speaking another language about me, and so on) from the other Team lead in a different department that I share an enclosed room with. I’ve brought this up to my manager and HR several times and they basically told me to deal with her because she’s been there longer and she’s an asset even if she’s been spoken to plenty of times about her bad behavior and attitude. She undermines my authority towards my team and takes jobs without notifying me. When I’ve tried speaking to her professionally about work, she blows me off and turns her body away. I don’t feel like my life will change unless I change it myself. I have anxiety and depression and take medications which helps but it’s harder and harder doing my job everyday. I am thinking of writing a resignation letter to turn in tomorrow. Please give me advice.