Who knows something about dogs?

I have a beautiful little Bichon Frise puppy that has had a bad past.She started out loved and pampered by her owner.When her original owner passed away,she was then treated fairly well by the original owner’s husband.After that, she was given to their son, who abused her and then she was passed on to their other son who abused her also.She was then passed on to me and I have loved and pampered her for 6 months now. We were originally told that she was 10 years old. When I first got her, I immediately noticed cataracts developing in her eyes. I also noticed that she seemed to have hearing problems. Recently, she’s started walking around in circles a lot which I’ve been told is a sign of brain damage. To my sudden and absolute despair, yesterday she had 2 seizures, one right after the other, and she was shaking for the rest of the day. Her hearing problems and sight issues have become much worse in the last week or so.She also suddenly has trouble climbing stairs.My mother, who knows quite a bit about all animals, dogs in particular, told me today that she has a strong feeling that my poor baby doesn’t have much longer to live.According to a good friend of her original owner, this dog is somewhere around 16 years old, contrary to the original estimate of the her son. My mother’s mother had a dog with epilepsy, also, that she ended up having to put down, and she has told my mother that she probably will die soon. I need an opinion from someone who knows something about dogs, because I don’t want to accept the fact that she will pass soon unless I get another opinion. I need the absolute truth, though.Don’t sugar-coat it.Help me please!