Planning a wedding is exciting.

Mapping out a vacation is fun.

Figuring how to afford care for your confused, elderly father? That one may never cross your mind — at least, not until you need more money to care for him.

"Never thought about it," Natasha Shamone-Gilmore, 58, says about her younger self. "Never ever."

She thinks about it a lot these days. Shamone-Gilmore, a computer trainer in Maryland, now shares a modest home with her husband, 24-year-old son and 81-year-old father.

Like millions of other middle-aged Americans, she had long regarded her parents as robust adults, more than capable of managing their own affairs. "My mom was a very active woman; my dad ... was a Safeway employee for 40-something years," she said.

But time does what it does, and today, her father needs a caretaker. So she has had to step into that role and figure out how to make it all work financially.