'Never Good Enough' for Mom and Dad

June 4 -- Sheri Petteys says her mother couldn't stop criticizing her — even on her deathbed.

The terminally ill woman, who was legally blind and could never realize her dream of being a nurse, had raised Petteys on her own after her husband died young, and hoped her daughter might fulfill the ambition denied her, Petteys said.

But that path never called to Petteys, and as her mother lay dying, the older woman found fault even in how Petteys handled the crank to adjust her bed, she said.

"She told the nurse I was doing it wrong," Petteys said, able to laugh, seven years after the fact, at that ultimate moment symbolizing years of her mother's disappointment.

"She had a very hard life," said the 42-year-old mother of two in Williamsburg, Va. "I think she was very frustrated."

It's a sort of frustration and disappointment that experts agree nearly all of us struggle with when parents' expectations don't match the reality of their offspring, and that disappointment can be a major problem, lingering even to the edge of death in Petteys' mother's case.

"I think part of it was she wanted what was best for me," said Petteys, who was one of scores of people who e-mailed their stories to ABCNEWS.com. "I think it's so hard for parents to separate guidance from shoving you into the slot [of their own ambitions]."

Healthy Expectations vs. Unrealistic Intrusions

Dealing with parents' disappointments is a nearly universal issue, says Susan Newman, a social psychologist and author of Nobody's Baby Now: Reinventing Your Adult Relationship With Your Mother and Father.

"We spend our lives trying to meet our parents' expectations, trying to make them happy," she said.

Expectations can range from the profound to the trivial. Parents may have issues with their children's career, marriage, city of residence, and decisions to have or not have children. They can also object to what clothes their adult children wear or the kind of cars they buy.

Parents only rarely decide they want to interfere or meddle in their adult children's lives, though, says Meri Wallace, the director of the Heights Center for Adult and Child Development in Brooklyn, N.Y., and author of Birth Order Blues.