my sister, who is 58 years of age has all of her adult life, lied to and about us - her family - and when we confront her about it, she shuts down, refuses to talk to us, and acts as if we don't exist. She can go for years with no communication. She will come back into the family when there is a big event - say a wedding or funeral, then before long, history with her lying and freezing us out begins again. Is this an emotional disorder with her ? What can we do ?