My mom wants to move, she lives near my sister paying 1700.00 a month far above her means. I agree with my mom and stated so
Then my sister blocked my moms phones so she couldn't call me. SoI purchased a cell phone so she could call me
My sister then told me she's nolonger my Sister and don't ever contact her( my sister) in anyway. How should I handle this she lives.39 miles from me with her boyfriend. I try not to break family ties but what can. I DO?

Obviously she has been trying to control your mom or keep moms attention to herself, and feels threatened. There is little you can do, I would be more worried about mom and if she is in control of herself at this point