Many AIDS advocates and workers are from gay organizations, and often the line between AIDS and gay rights issues is blurred. Among some uninfected men, so is AIDS and their homosexual identity. In the public's mind, to be sure, it is often assumed that to be gay is to have H.I.V. and as a result both infected and uninfected men have suffered similar problems, like AIDS-related discrimination.

Many gay men who do not have the virus have lovers and friends who do, and often postpone their own lives while seeing the sick through the illness. Sexuality has been redefined, with health concerns providing the backdrop for sexual encounters. One of the most debated issues among H.I.V.-negative men, some say, is how safe oral sex is and at what point it becomes unsafe.

Some men are gripped by such fears of acquiring the virus that they lose sexual drive. Others agonize over the slightest physical change, and have themselves tested for H.I.V. several times a year.

The interior designer who does volunteer AIDS work says he has been celibate for the last two years. The man says AIDS has stirred up deep-seated feelings, like shame over being gay. But he says he is mostly depressed over so many dead friends, so many that he no longer keeps track of them in his journal.

"I feel very old," said the man, who will attend Mr. Ball's support group. "I feel this gap between me and the rest of the gay population."

Some men, unable to focus on their own lives, live as if they themselves are dying: they cannot make long-term plans, like pursuing a college degree, mental health professionals say. And it is a sense of fatalism, some health workers say, that lead some to not use condoms. When there is no future the consequences of actions lose importance.

The number of reported AIDS cases among gay and bisexual men has declined nationwide in recent years, pointing at the success of prevention efforts. But several studies have documented a relapse to risky sexual practices, like anal intercourse without condoms, among men who had previously protected themselves to avoid H.I.V.