I don't feel close to my mom anymore. What to do?

My mom is 81 years old and lives on her own. I use to feel close to her, up until about 2 years ago. She is not very affectionate and fusses and complains a lot. She lies a lot too and is rude, critical, and expects her kids to do so much for her. She is demanding and selfish too. I lived near her my whole life and decided to move to another town, 2.5 hours from her with my son. Just wanted to try something different. She has a history of mental illness and has bipolar tendencies and cannot control her tongue. If I speak how I feel, she hangs up the phone. I am always walking on egg shells with her and just decided it would stop. I feel I needed to start a different pattern in my relationship with her. My 5 other siblings know how difficult she is and just put up with it or don't call her, sometimes for a month at a time. It is sad because she is old and needs caring but I lost how I feel because she is just so mean all the time. I still have a dedication because she is my mom, but I just had to step back and reevaluate our whole relationship and really see it for what it is which is not that much anymore.