My sincere condolences to you mate
I know what that suffering is,my mother died 3 years ago ,at the age of 89.
In the last 15 years she was unable to do her normal life,she suffer for arteriosclerosis also, and in the last four years of her life she stay in bed almost all the time- fortunately I had some professional care to help me to take good care for her needs,but it was a lot of pain and suffering seem someone you love slowly losing her capabilities and quality of life
but, above all, you should be happy for all the love and affection and support that you gave to her ,until the end of her days.
I know that in these firsts days you will be in a lot of sorrow and pain,be strong and if you are a believer ,like me,you will know that she now is in a much better,peacefully place