Nashua, N.H. — Shortly after Jenny and John Seussing got married, they found their promising careers had turned into dead-end, low-paying jobs. The bills began to pile up and the walls of their newly purchased home seemed to close in on them.
About the same time, Jenny's parents were going through a divorce. It became apparent that her mother could not afford to hold onto the family house in Nashua without financial help.
The solution to both their dilemmas seemed obvious. The Seussings moved in with Jenny's mother. They've maintained ownership of their own house by renting it out, and Jenny's mother has been able to keep her house with the modest rent the Seussings pay her.
The arrangement has worked so well over the last 16 months that even though John has a new job as a Nashua policeman and Jenny has moved into a marketing position with a local firm, they plan to stay there until her brother graduates from high school later this year. Then they'll all go their separate ways, with Jenny's mother moving into a smaller house or apartment.
Across the country, young married couples like John and Jenny Seussing, caught between a stagnant economy and a tight housing market, are going back to where the rent is low and the rooms empty: home, to mom and dad.
''It's the new GI Bill,'' says George Sternlieb, director of the Center for Urban Policy Research at Rutgers University. ''Good In-laws.''
Available statistics do not show a widespread migration back home on the part of young couples. US Census Bureau figures indicate the number of married couples sharing a home with relatives rose modestly to 625,000 couples in early 1982, up from 580,000 each of the previous two years. Still, demographers and sociologists believe the greatest jump has occurred over the course of the last 12 months, which won't show up in census records until June.
In addition, a recent upturn in housing starts and a lowering of interest rates may affect the number of couples moving home - or moving back out after being home.
The phenomenon appears to stretch across all economic lines. ''We've suspected for a long time that married couples were moving back in with parents. But the pattern was virtually nonexistent except in certain economic groups. Now it's ubiquitous,'' says Sandra Howell, professor of behavioral sciences at Massachusetts Institute of Technology.
However large or small the movement home may be, the decision to move in with parents is at best a difficult one and usually taken as a last resort.
''Sometimes I think: If I could really handle things on my own I wouldn't be here,'' says Jenny Seussing. ''Then my husband convinces me it's right for now.''
The lack of a job - or a well-paying job - is an obvious and primary motive for moving home. But others see the lack of new homebuilding in recent years as a chief culprit.
Patrick H. Hair, head of a Washington, D.C., consulting firm, maintains that the baby-boom generation is reaching its peak rate of household formation, which is greater than the number of new and renovated housing units coming onto the market each year. The result: ''We're underbuilding by 50 percent a year,'' he says.
As this generation gets married and couples begin their search for scarce housing, they leave behind parents with large, empty houses. Mr. Hair says that this scenario, combined with a tight job market, is bound to create at least a minor backflow of young marrieds to parental homes.
Though most couples don't encounter the difficulties Gloria and Mike Stivic did when they moved back in with televison's Archie Bunker, problems can arise when three or four related adults find themselves living under one roof.
''It's hard to keep your marriage separate from your family,'' says Deborah Nickerson who, along with her husband, moved in with her mother-in-law and teen-age sister-in-law in Newton Highlands, Mass. ''The little things start to add up, and sometimes they reach the boiling point.''
The lack of privacy is one problem. Mrs. Nickerson tells of married friends living at home who are made to feel that ''they owe their parents something'' for the arrangement. And while some parents feel privileged to have children home, others feel burdened by the experience.
Sociologists are still trying to decide whether or not the phenomenon is a trend or a statistical aberration tied to the economy. Says George Masnick, an associate professor of behavioral sciences at Harvard University:
''I rank this phenomenon in the category of homeless people. It's definitely happening and worth taking note of, but it is a rare, statistical phenomenon that is probably temporary. Society says that you haven't really made the transition to adulthood until you're on your own. That's a pretty strong incentive to try to do just that.''