The world won't hold still for Debbie Howell.

Window blinds always flutter, the ground rises and sinks like ocean waves. Every chair is a rocking chair.

"One of my biggest problems is looking down," says Howell, 34. "I feel like I'm falling forward. I'm not. But it's such an overwhelming feeling that I can't just tell myself I'm not falling."

Because of a head injury in a car crash in 1984, the balance mechanism in her right ear doesn't work normally. Any sudden turn of her head brings dizziness.

Howell continually wobbles, even standing on firm ground, because she is constantly getting false readings of her surroundings. Things seem to be spinning or shifting or tilting even when they're not.

"Basically, it's like flying in the clouds without instruments," says her husband, Dennis.

Six years ago, 11 months after the birth of her daughter, Tiffany, Howell was knocked semiconscious in a car accident when her head hit the windshield. She was in the hospital less than a day and seemed to recover quickly, with only a whiplash in her neck. But nine months later, she developed severe dizziness that has never gone away.

"It has devastated our way of life," says Dennis Howell.

Despite a love for travel, the Howells rarely venture more than 20 or 30 miles from their home in Aurora, Colo., near Denver.

"I doubt I'll ever fly in an airplane again," Debbie Howell says. "I'm sure I'll never ski." And "needless to say, we got rid of the waterbed."

Two weeks ago, she went bowling for the first time since becoming dizzy. Her score was a modest 110, but it may have been the finest game of her life.

Movies were out of the question for three years. Now it depends on the day and the movie: " 'Pretty Woman' didn't bother me at all, but "Back to the Future III" -- I had to get up and leave."

It was nearly three years before Debbie Howell could even get a diagnosis for what had thrown her life into chaos. She ping-ponged from doctor to doctor before specialists at Good Samaritan Medical Center in Portland, Ore., finally pinned it down. An inner ear concussion had torn a leak in the window between the middle and inner ear -- a condition known as perilymph fistula.

She has had four operations on her inner ear, but none succeeded in repairing the fistula. Tranquilizers and motion sickness medications have helped take the edge off her dizziness, but it's always there.

"Sometimes, on a good day, I'll get really engrossed in something and forget about it a while -- until I turn my head and feel like I'm falling again," Howell says.

"Disorientation is a disabling illness," says F. Owen Black, the neuro-otologist in Portland, Ore., who diagnosed Howell. While many cases respond to treatment, Howell's is an example of how devastating dizziness can be.

The struggle back toward a semblance of normal life is marked by painful reminders -- and small triumphs. Last summer Howell went swimming -- "with my head up, like a dog paddle." She goes to the store a couple of times a week. Most evenings, she reads for up to half an hour or until eye strain threatens to bring on motion sickness. She used to sit only on the floor -- "it was a solid surface my brain could latch on to" -- but now manages a hard chair pretty well.

"I try to do everything normal people do," Howell says. "I just do it as long as I can, and then I have to quit."

Partly out of frustration with his wife's experience, Dennis Howell helped start a regional support group for people with dizziness or balance problems. Every month, he goes to the group's meeting.

Debbie Howell stays home. "I want to try to be as normal as possible," she says. "I don't want to sit around and talk about being dizzy."