Well, mine survived it by getting divorced. My grandparents slept in different beds, watched t.v. in different rooms, and granddad would do a lot of woodwork in the basement. He got real bad hearing loss from running loud saws all the time without hearing protection. My other grandparents, I don't know, they always argued, granddad always picked on grandma and I think she learned to pretend to be deaf but I think granddad always knew she could really hear him. He always knew what buttons to press to make her hurt the most.
My granddad didn't bother to tell my grandmother he was divorcing her, and intended to do so during a school function of my mother's. The lawyer, however, delivered the paperwork a day early and he wasn't packed yet, so what he thought would be a smooth sailing turned out to be much more uncomfortable than he would have preferred.
This same man sold a million dollar sawmill for pennies on the dollar because he really just wanted to be an accountant. The most boring man of all time.
My mom's parents were in love with each other until the day my grandmother died which was the only time I ever saw my grandfather, who survived the Bataan Death March, cry.
My dad's parents announced they only had a couple years left to live about five years ago and promptly sold their house; my grandmother moving into a retirement home and my grandfather moving into an apartment about five minutes away.