So sorry that you got this news. Doctors give a timeframe to get you ready but noone knows for sure what or when or if. The only adivse i can give from someone who lost their Mom to this (she survived more that a year after the 6 months they originally gave her )is to love and enjoy her now. Tell her everything you want to tell her and let her do the same with you if she wants. You may not tell her but her body may give her signals at some point. Then she will really need someone to talk to. I have no regrets as I promised my Mom when she did start to know that i would "see her gently into that good night" just as she saw me gently into the world when she gave birth to me. May God bless you, your Mom and your family