May God gives you the courage to overcome this news . Stay positive and listen to doctors . Hope there will a way , she will fight it . 

Hello sunflowers01; welcome to this forum.  I am sorry to learn that you have had this terrible shock re your mum.  I imagine the doctors will be able to give you an estimate of how long your mum may have but it - in my experience with friends and family - is a bit uncertain as different people can with the same conditions can vary in the amount of time they have.  Just make the most of your time with your dear mum, listen to her, tell her how much you love her and care for her no matter what (I am sure you are doing this anyway).  Do let us know how things are going if it helps you to post here; we are always willing to talk things through here.  Annie