HERE are two novels that provide fresh insights into an age-old problem, the fragile alliance of a man and woman who are ultimately only ''the most intimate of strangers,'' as Janettecq Turner Hospital put it in ''The Ivory Swing,'' another fine first novel about marriage.
Alice Reese, the 33-year-old heroine of ''Dreams of Sleep,'' has recently learned that Will, her gynecologist husband, is having an affair with his receptionist. After the initial rush of jealousy, ''when a woman's obsession with her rival tends to resemble love,'' Alice slips into lassitude.
Back in Alice and Will's college days, it had been Will who insisted on marriage, a marriage that ''had to be everything.'' Now he has come to believe that ''the loneliness of marriage, the thing Alice had so feared, starts out of the love itself, which can never deliver on its promises.''
Alice's mother-in-law tries to rouse Alice from her torpor by suggesting she hire a baby sitter to take care of the Reeses' two little daughters in the afternoons so Alice can get out of the house. Enter 17-year-old Iris Moon, whose shattered family life has made her determined to invent her own family by kidnapping the Reeses' daughters.
The setting is Charleston, S.C., a city with a languid image that reflects perfectly the book's passive mood. But it is also a city in transition; the Old South is being assaulted by outside investors - Will's stepfather plans to build a ''theme park'' - and this threat of disintegration pervades the book.
''Dreams of Sleep'' is beautifully written, intelligent, and evocative.
Calvin Hart, the hero of ''The Divorce Sonnets,'' is as lonely as the Reeses, but he disguises his loneliness with nonstop talking (''Oh, when talking he told nothing!'') and with such costumes as a planter's suit and pith helmet. Like Will Reese, at the outset of a romance he is obsessed with the woman; unlike Will, he keeps marrying them.
In the 30-year span of this novel, during which Calvin leaves Connecticut, graduates from Columbia, and becomes a talk-show host in Indianapolis, he marries four women: Kasey, a teen-age ballerina whose elusiveness attracts him; no-nonsense Fern; Sheila, whose possessiveness he at first relishes; and, full-circle, another teen-ager, Lisa, who seeks inner and outer order. Different though his wives may seem, they have many similarities, the most important of which is humorlessness, a warning sign indeed!
Calvin's ironic outlook must supply the fun in this book, and it's here aplenty, as when he describes his grandfather's caution about money: ''Able Thomas had also chained several snarling bankers around the fund, ready to go for Calvin's throat if he touched it before college.''
His grandfather, grandmother, and great-grandmother are the touchstones to which Calvin keeps returning in his monologues - and eventually in person, to the family's Cape Cod roots where he hopes to learn at last how to cope.
Although its subject is breakups, ''The Divorce Sonnets'' is a solid novel, packed with satisfying images and observations.