Marilyn Machlowitz loves her work so much she finds it hard to pull herself away from her desk.

She tells this story:

One Saturday night, she planned a special dinner date. She would do the cooking; her date was due at 6:30 p.m. She arose at 6 a.m. to put in some extra hours on a writing project. She got so involved it was 6 p.m. before she noticed the clock.

"I called my friend and asked him if he would come over at 7 . . . After all, I had not yet even dressed that day, let alone made dinner."

At 6:30, she phoned him again. Would he "please stop at the deli on his way over and buy something for us to eat."

Machlowitz is, she confesses, a "workaholic." What she put her date through that Saturday night is the sort of thing spouses and children of workaholics frequently experience, often unhappily.

Washington, she notes, attracts workaholics. The 60- to 70-hour weeks on Capitol Hill and in law offices are, to one psychiatrist, "as American as apple pie."

A staff psychologist (Yale doctorate) with the New York Life Insurance Company, Machlowitz, 27, has a new book out on the subject, "Workaholism" (Addison-Wesley, 189 pages, $10.95 hardcover, $5.95 paperback).

She found in her research that it's not the workaholic who suffers because of these long hours. It's the people they live and work with. "At home, well," she says, "you'll seldom find a workaholic at home."

In interviews with work addicts across the country, Machlowitz concluded they are not the burnt-out wrecks you might expect. Instead, they are reasonably happy people "who love to work, who live to work, who can barely leave their work." They seldom take vacations and many "climb the walls on Sundays."

Though this cn be upsetting to others in the family, her view is workaholics "are lucky to like what they do enough to live for the 50 weeks a year that they're working, rather than fantasize about the two weeks a year that they're off."

Her idea of a job, she says, "is something you do for free. The pay is icing on the cake."

While probably the great majority of us "thank God, it's Friday," Machlowitz's associates, knowing her beliefs, gave her a T-shirt with a slight variaition. It read, "Thank God, it's Monday." On the back: "To rest is to rust."

Workaholics, maintains Machlowitz, have gotten a bad rap for several reasons. First is the word itself and it's similarity to another human excess. She has on at least one occasion been introduced -- quite wrongly -- as an alcoholic.

Another is the "envy and anxiety of coworkers concerned about getting half as far as those who work twice as hard."

And, she adds, "There is the anger of those at home who have to cope with and compensate for what the workaholic won't do."

So far, she writes, "The evidence is still inconclusive as to whether involvement in work inevitably and invariably exists at the cost of involvement at home."

But, she says, the workaholics she interviewed "spoke of success only in relation to their work; their feelings of failure were usually family-related." r

Many wives of workaholics she interviewed complained that their husbands "cared more for their work than for them." A magazine editor "could recall with precision the number of hours he had worked the week before (80)," but not the number of years he had been married.

One man made the effort to take his children to weekend sporting events at a stadium. "So there he sat, with one child on each side of him and a stack of business reports and other reading in his lap."

Another problem, says Machlowitz, is that people "who can't bear to lose control over the smallest detail at work, readily relinquish this role at home." She is quick to point out, however, that often the couple met at work. "Spouses usually knew what was in store."

The disappointment comes when the workaholic continues to work as hard after marriage as before. The unhappy spouse is left to comment, "Gee, I thought this would change at 35, or when we had kids. It didn't."

Her advice to family members trying to get more time with the workaholic is, she says, "unusual." Traditionally, a wife is told, "Get hubby a hobby." But a hobby can become merely a substitute for long hours on the job. "Is it going to be any easier to have a marathon maniac at home?"

She says the family should "realize that the work addict won't change. What usually happens is that the workaholic's work pattern persists and the family adjusts."

Machlowitz's guidelines for adjusting:

Schedule time together with the workaholic -- the way Jimmy Carter finds time for lunch dates with Rosalynn. "Marking these in the calendar in ink will make them almost as sacrosanct as business appointments.

Have the kids accompany the workaholic to the office on the weekend. Often "it can be exciting" for them. Children can end up "resenting their parents' work because they don't understand it -- why Mom and Dad are away all day."

Provide reassurance. Tell the workaholic spouse "You'll love him (or her) twice as much if they work half as much or earn half as much -- if that's true."

"Simplify and streamline domestic drudgery" so you don't expect the workaholic to pitch in.

(Machlowitz, to set the example, lives in a spartanly furnished apartment -- "I call it High Tech: others says its barren": hires someone to clean it; orders groceries by phone; walks to work, and is "very content to open a can of tuna fish for dinner.")

Insist on vacations. Limit calls from the office, leave the briefcase at home.Start with five days and build to two weeks.

"Anticipate spending a lot of time alone."