My Nana was the same way, for slightly different reasons . She socked away a TON of money when my mom and her siblings were kids, to the point where they lived VERY modestly, because she was always worried about her husband being unable to work due to his health.
He was able to retire at age 60, so she planned well!
But she always felt guilty, like she had deprived her children (my mom said that she never felt that they had gone without) and made up for it later in life.
I currently live in her old condo, which she sold to my mom for 2$ :)