It's as if she went underground or vanished into the sea," comments a longtime acquaintance of Pat Nixon in Washington. Since her husband's public disgrace the former First Lady has concealed herself relentlessly.

In the few times she has been glimpsed in public, her tightly drawn smile and stiffly regal bearing have not betrayed her private feelings. Now, isolated from all but her supportive daughters and a handful of familiars at Casa Pacifica, Pat occasionally slips away for solitary walks on the beach—or to be driven down the coast to visit a girlhood friend, Helene Drown, wife of a Rolling Hills magazine distributor.

Mrs. Nixon endures the burden of her husband's illness and political exile with the same quiet determination and unquestioning loyalty that have become her trademark. (Once, four months before her husband's forced resignation, she proposed that he burn the incriminating Watergate tapes. That advice, of course, went unheeded.) Still, the loyal helpmate stands by, spending hours every day by the former President's sickbed. When he is not listening to sports on the radio, Pat reads to him—as she did during her daily hospital visits—from the mail which continues to pour into the erstwhile Western White House. She dutifully oversees the bland diet to which Nixon is restricted, urging him to gain weight, trying to make dinnertime a cheerful pause in the empty, dragging days. When she has a moment to herself, she works on her memoirs.

Last week Pat briefly sipped Christmas champagne with local volunteers who help out with the mail (PEOPLE, Nov. 25). But when one of them asked to take her photograph as a memento, Mrs. Nixon begged off, without explanation. Perhaps it was her painful thinness. Nonetheless, an old friend insists that "her health is marvelous. Pat has always coped and done the best. That's what she's doing now."

Mrs. Nixon has been worried about her husband's dwindling financial resources and legal entanglements. To cut maintenance costs at San Clemente, Pat—in tennis shoes and Levi's—is uprooting its acre of rosebushes and donating them to public institutions. Says son-in-law David Eisenhower: "I don't know how she's held up this year—but she has. Now, in a very sad, tragic way, she has the peace and quiet at San Clemente that she has always wanted."