Mary Kidd had directed one of the District's best-known agencies for helping alcohol and drug abusers for several years when she found out that her daughter had a drinking problem.

"I just didn't believe it. I was supposed to be an expert, but I didn't know she had a problem," Kidd recalled recently. "It is extremely difficult to pin down, especially in the family. But once I understood her problem, I knew what to do."

Kidd joined a local chapter of Al-Anon that helps relatives of alcoholics. There, she said, she came to understand fully the meaning of the advice she had often given to others: "The bad news is that you can't make them stop. The good news is that you have to live your own life."

Kidd tells the painful story as she leaves after 13 years as executive director of the Washington Area Council on Alcohol and Drug Abuse (WACADA), which operates the area's only 24-hour hot line for alcohol and drug abusers and monitors the effectiveness of government programs to combat drug abuse.

Kidd's duties included everything from fund-raising to testifying before congressional committees to occasionally manning the hot lines that logged 24,300 calls between June 30, 1983 and June 30 of this year.

But a heart condition and rheumatoid arthritis have slowed down the 51-year-old former Anacostia resident and neighborhood organizer, forcing her into early retirement from her $39,500-a-year post.

"It's a bloody nuisance," Kidd said of her afflictions, which require regular medication. "Whenever I go to a meeting, when I walk a few steps, I take a nitro capsule , take a few more steps, stop and do it again. It's a pain in the neck."

Seated in a tall office chair that elevated her feet, Kidd spoke energetically of her years with WACADA, showing little indication of her ailments, except for a slight shortness of breath.

Although she knew of her sickness for months, she continued her day-to-day duties for the $600,000-a-year program until her doctors told her to stop.

"This is a stressful job, which makes it more interesting," she said, in her office at WACADA headquarters, 1232 M St. NW. "You feel like it's right on the edge of collapse all the time. But it's good to at least make the effort and that someone is trying."

Kidd joined WACADA in 1971, when the program had already won its campaign to get the District to treat alcoholism as a disease and to offer medical care, instead of as a crime punishable by jail sentences. But she fears that the more enlightened treatment of alcoholics is being eroded by current calls for harsher penalties for drunk drivers.

"We had alcoholism recognized as an illness, but the country is retreating from it," she said. "Most of what has gone into the effort against drunk driving is enforcement and increasing penalties . . . . However, at least half the people who are DWI driving while intoxicated are people with a serious problem. Addictive people are not affected by these measures at all, but it's in tune with the times."

The drug scene also has changed. Thirteen years ago, heroin was the city's most popular and dangerous drug. Today, Kidd said, problems with cocaine and PCP are mentioned most often by those who call WACADA's hot line.

The city has increased its treatment and its training programs in response to the growing use of PCP, she said, but she sees a resistance to responding the same way to cocaine abuse.

"I think that there is a belief that cocaine is so entrenched in social circles and that there would be embarrassment if they were to jump on cocaine," she said. "PCP is used by kids a lot. It's a poor person's drug. And youngsters on PCP are easier targets for treatment."

A veteran social activist, Kidd became a poverty worker for the Great Society in 1966. She helped organize a neighborhood medical clinic, which still exists on W Street SE, where she lived with her husband Donald, a professor of physics at Gallaudet College.

Her husband died later that year. Her son, Ronald, now 32, who is deaf and retarded, lives at St. Elizabeths Hospital.

When Kidd learned that her daughter was an alcoholic and had been drinking heavily since her early teens, she said she at first reacted irrationally and tried too hard to find a reason.

"I used to think, 'This girl is mad at me. She is going to drink just to embarrass me.' Now that was just crazy," Kidd said. "I was terrified when she wanted to drink something. I talked to her about going to AA Alcoholics Anonymous once and she said, 'It's none of your damn business.' I learned later it was very arrogant to assume you have the right to control someone like that."

Kidd learned to become less obsessive about her daughter and more positive about herself. The daughter got rid of her drinking problem and now manages an animal emergency clinic in Los Angeles.

"I got help for myself. Then she got help for herself," Kidd said. "She really deserves credit for her recovery. So when I get on the hot line and I get a parent on the phone with the same problem, I say, 'You're so lucky you got me.' "

Kidd left WACADA on Nov. 15. She and her son plan to move to Summerland in British Columbia.

Her social activism will continue despite her physical ailments. "I'll always have the belief that there will be something for me to do," she said.