BOB BERGERON was so relentlessly cheery that people sometimes found it off-putting. If you ran into him at the David Barton Gym on West 23rd Street, where he worked out nearly ever morning at 7, and you complained about the rain, he would smile and say you’d be better off focusing on a problem you could fix.

That’s how Mr. Bergeron was as a therapist as well, always upbeat, somewhat less focused on getting to the root of his clients’ feelings than altering behavior patterns that were detrimental to them: therapy from the outside-in.

Over the last decade, he built a thriving private practice, treating well-to-do gay men for everything from anxiety to coping with H.I.V. Mr. Bergeron had also begun work as a motivational speaker, giving talks at gay and lesbian centers in Los Angeles and Chicago. In February, Magnus Books, a publisher specializing in gay literature, was scheduled to print a self-help guide he had written, “The Right Side of Forty: The Complete Guide to Happiness for Gay Men at Midlife and Beyond.”

It was a topic he knew something about. Having come out as gay in the mid-1980s, Mr. Bergeron, 49, had witnessed the worst years of the AIDS epidemic and emerged on the other side. He had also seen how few public examples there were of gay men growing older gracefully.