The voice on the telephone was so low it was barely perceptible. The caller asked me to hold on while she went to a more private desk. She was calling in reaction to a recent column about how differing shades of skin color had come between some blacks and made them live in a separation of hues. "I'm a white-appearing black who is passing for white and I don't want anybody to hear, but I want to tell my story," she said.

"Passing" has always been a deeply controversial phenomenon in the black community. In years past, some blacks passed to obtain jobs that were closed to blacks or to enter certain social circles. Since the civil rights movement, it has been pretty much a thing of the past. What's unusual about this woman with the straight black hair and lightly freckled, olive complexion is that she's passing in 1982, and her decision had nothing to do with employment. "I did it for my sanity," she said.

Because of family rejection, her image of herself was always weak. The historical images she sought out, for example, were not the black civilization at Timbuktu or black contributions to culture, but rather the elitist, light-skinned quadroon society of New Orleans. When she might have been absorbing the culture that liberates and creates self-esteem, she was caught up in conflict.

She has been passing for white in Washington for 12 years, but still feels in turmoil because she does not want to cut all ties with her family even though she feels rejected by them and by other blacks who think she is too white-looking.

She was the first white-appearing black in her family in 30 years when she was born 35 years ago in a southern city. Her light-skinned brother was born later. She never knew her father and she lived with her grandparents from an early age. Family resentment of her and her brother focused on skin color as well as illegitimacy. She recalls standing in line in second grade when an older girl said, "This girl is in the wrong school. She should be in the white school."

Few of the girls at the all-girl high school she attended were friendly, mistaking her painful shyness as snobbery. A white Jesuit priest suggested that she pass and she rejected it, but perhaps the seed was planted. She came to Washington in 1967, at age 19, and moved in black social circles.

While rejection by blacks had made her life difficult before, it became almost unbearable between 1967 and 1970, as the revolution of black consciousness unfolded. As blacks donned symbolic dashikis, wore Afros and called for black power, she found, "I was not black enough. I tried wearing a curly hairdo for a while but somebody asked me why I was wearing a wig. I tried the black slang for a while, but I did not like it and soon gave up." She left Howard University after only a year because she was often the only white-appearing person in class and felt she was "treated differently."

Black men posed a special problem. "I gave up on them because I found they treated me differently, too. One guy took his revenge for whites out on me. I got fed up with trying to bounce back and forth, trying to prove to blacks that I was one of them. It became a nuisance."

She crossed over in 1970. "I decided to be white. I said, what the heck? What am I fighting for? I let it go." She moved from her predominantly black neighborhood to the suburbs, dropped her black acquaintances except for a couple of close friends, stopped going to black social events, started dating only white men.

"At first it was hard to contain my emotions and thoughts when white friends spoke badly of blacks . . . . My friends called me a 'martyr for the black race.' "

Dealing with her family was less difficult. She was already estranged from her mother, who works in the Washington area, but "doesn't want to acknowledge me as her daughter . . . . She refers to me as a friend." They talk on the telephone about family gossip, but they don't visit and neither acknowledges she is passing. Her mother knows about it from other family members.

Her brother married a brown-skinned woman and lives his life as a black in another city.

She says she is satisfied with her decision and feels "happier" now than before, a process that has been helped along by a black therapist, but the conflicts ebb and flow like a turbulent river.

"I've had a lot of trouble knowing who I am. But I come from blacks and whites. Why can't I enjoy both sides? Why do I have to be either black or white? Why do I have to choose sides?