I'm 15, I live with mom and grandma. My mom is disgusted my her's (my grandma) and always shows it...?

And you know how you learn by example? Well that's all I see, is my mom complaining, saying how disgusted she is with her (my grandma left her as a kid) and she has hatred for her. As ive gotten older, my mom has expressed to me (now everyday) how much she resents her. She just always is complaining about her, and I honestly can't help nut I've noticed now I am getting disgusted with MY mom... Just like her and her mom. I don't know what to do, but it's all I see around here. And if I tried o tel her that shed take it personally and get all mad and say "well what do u want me to do blah blah blah nag nah nag".... What do I do, I dont wanna be like her...