Peter O'Brien, real estate salesman, homeowner, father of four, is not unemployed. He is not bankrupt. The mortgage on his $275,000 house in Fairfax Station is current. By most standards, O'Brien and his wife, Mary, appear to be unscathed by the recession; they are the kind of Washingtonians unemployed auto workers love to hate.

In fact, in the last year and a half the O'Briens have gone from making it to just making it. Peter O'Brien's salary has shrunk from $70,000 to $30,000. Their teen-age daughters buy their blue jeans in thrift shops, and O'Brien has been forced to borrow money from family and friends to pay his debts. He and his wife have made no major purchases in three years.

At one point, the electricity and telephone in the O'Brien family's home were cut off. "The candles were taken out . . . and we made soup," says Mary O'Brien. She has gone to work as a substitute teacher at a day-care center, and finds herself wishing the house were "half its size, so we could buy some clothes."

The O'Briens are among the lesser victims of hard times. The recession has not yet leveled their lives, but it has chipped relentlessly into their savings, their confidence and their pride.

A recent Washington Post-ABC News Poll found there were more than 12 million such families around the country who reported significant drops in income last year after loss of bonuses and overtime hours. For these families and others less directly affected but anxious about the future, the recession has meant a series of choices, deciding when to do with less, and when to do without.

"The psychological effect is actually greater than you might think," says Chicago retail analyst Jay A. Levine. "If you're working in an industry that's come on hard times, you're a little worried. If your company has cut back 10 percent, you're very worried. It has a ripple effect . . . . Those who've retained jobs and have seen white-collar layoffs think twice about spending."

P. Wesley Foster, president of Long & Foster Realtors, sees that lack of confidence in the Washington real estate market. "People are not buying . . . , " he says, "out of fear that 'I could be next.' "

Many who imagined they were set for life are shocked to find security is ephemeral. Preoccupation with the present crowds out all thoughts of the future.

Sandra Bowers, for example, has a secure job as a technician at Children's Hospital and manages to pay her daughter's tuition at Holy Name School and keep the family's 1969 Volkswagen running.

But, she says, "I've just stopped planning. I don't have that confidence in tomorrow."

Bowers, 30, put herself through a business administration course at Southeastern College, but no longer thinks about opening her own business. "Just to keep going is all I ask," she says. "Just to keep up with the medical and dental bills."

The effect of choices being made "just to keep up" can be felt throughout the Washington area.

People are using public services rather than pay for such items as books, childhood shots and counseling. At Pacquin School, Baltimore's junior and senior high for pregnant teen-agers, enrollment is 1,200, a 500-student increase from 1981. The attraction, explains director Rosetta Stith, is the school's free prenatal care.

Local libraries are struggling with newfound popularity. Last year in Prince George's County, for example, the number of magazines and other periodicals that circulated inside the library increased by 42,000 over the year before. Some branches are so crowded that people have to lean against the posts and read.

Some choices are more personal, and more profound, than a trip to the local library. Newspaper photographer Larry Nighswander and his wife, Marci, have a recession-forced long-distance marriage, and it's not the stuff of jet-set fiction. After 12 years at the Cleveland Press, Nighswander was laid off last July when the newspaper closed due to declining advertising revenues. Since then, Nighswander has been living in a $430 apartment in Gaithersburg with two fellow Press photographers, all of whom were hired by the Washington Times.

Every weekend, Nighswander travels back to see his wife, who has kept her photographer's job at the Akron Beacon Journal. "Our life has lost its rhythm, with everything up and down," he says. "No one likes that."

Long-distance telephone bills, $240 round-trip air fares and gasoline for the all-day drive are a financial strain, says Nighswander, but he didn't want his wife to quit her job "in the vague hope she'd get a job in Washington. The job market's tough everywhere."

Others are also unwilling to take risks on the chance that the economy will support them. "It's no longer the case that people will make decisions on the basis of hopes for the future," says F. Thomas Juster, director of the University of Michigan's Institute for Social Research, who has been monitoring national consumer attitudes for 30 years. "They've been burned enough by economists, politicians and forecasters, and now they want to see an improvement in place as well as prospects."

Of course, to some Washingtonians the recession has meant an abundance of good bargains in clothes and consumer goods. "People have heard so much about how business is bad that they are unbelievably conscious of sales," says Woodies vice president James R. Wells. "We have some very rich customers looking for sale items right alongside people with lower incomes."

Luxury grocery stores with packed aisles are signs of what Chase Econometrics analyst Sandra Shaber calls "the Mercedes phenomenon." Sales of so-called "sexy goods," video machines and computers, have remained high. "The expensive items have held up well in this recession," she says. "It's the middle market that collapsed."

Still, in hard times, consumption is more likely to seem conspicuous, and along with their bills some wealthy Washingtonians, at least, have made ceremonial bows to the recession. "I don't feel comfortable spending, even though I can afford it," says Carol Marchesano, president of Goldberg Marchesano & Associates, a Washington advertising firm.

John Orcini, owner of Avignone Freres, a catering firm, says he has fewer clients and that at many parties roast beef has replaced filet mignon. Bruce Ellis, co-owner of Ridgewell's Caterers, says more Washingtonians are giving up seated French service dinners for cocktail parties.

He says some clients tell him, " 'I can afford sliced tenderloin and whole loin of plume de veau veal , but this isn't the time for that. People might get the wrong idea.' "