The woman closest to John A. Paisley over the past two years described the ex-CIA official yesterday as a quiet man who had passed through bouts of suicidal depression but who was, at the time of his death, "the happiest I'd seen."

In an interview, Betty R. Myers, 51, also disputed a Maryland State Police assumption concerning the pistol Paisley was known to have kept abroad his sailboat. Paisley disappeared while sailing on the boat Sept. 24 and a week later his boat, with a bullet in the head, was found floating in the Chesapeake Bay.

Meyers said yesterday that Paisley has sold the 9mm automatic pistol this summer. "That gun was not on the boat. John kept it in my apartment this summer and took it away when he told me he had sold it to somebody," Myers said.

Myers' statement about the gun heightened the mystery surrounding Paisley's death in light of a Maryland State Police announcement yesterday of ballistic findings showing the Paisley was killed by a 9mm bullet.

Police spokesman William E. Clark said the seven-man team investigating Paisley's death, which met yesterday in Pikesville, Md., to review the case, hasn't been able to confirm that Paisler did sell his pistol this summer.

Clark said that if Paisley had sold the pistol to a private individual, there wouldn't necessarily be any record of the sale.

"We have no significant leads that we are pursuing in the investigation," Clark said. "Unless something dramatic comes up, we just won't be able to tell whether Paisley's death was suicide or murder."

Betty Myers, who said she had been in a "close relationship" with Paisley for two years, frequently mentioned during the interview that the last few months before Paisley's death "were the happiest times for him that I'd seen."

But Myers, a psychiatric social worker who took a job in Cumberland, Md., the week before Paisley disappeared, said that Paisley was not a man who openly expressed his feelings.

"John was a private person. I sometimes wished for him to talk to me more about what moved him. When things were important to him it was difficult for him to talk about it with others," Myers said.

She said that Paisley, 55, who retired in 1974 from the CIA's Office of Strategic Research and who remained with the agency as a consultant, was deeply depressed two years ago and spoke of suicide.

"He realized he was growing older, he'd left his job, his kids were growing up and he was leaving a marriage that had once brought him grate happiness," Myers said.

In the ensuing two years, Myers said, Paisley appeared happy and seemed to adjust to the changes in his life. He attended an encounter session called Lifespring 1st December and again in March. "Lifespring changed his considerably; he worked on being more open," Myers said.

The week before Paisley disappeared, Myers said, she spoke with him times on the phone and they discussed her move to a new job in Cumberland.

"It was the first weekend we'd been apart for six months.He said he was going to do some sailing and try to finish a paper," Myers said. Paisley was writing a paper as part of his CIA consulting work about the recent problems of the B-1 bomber project in getting congressional and presidential approval, according to Myers.

Paisley's sailboat, the Brillig, was found aground and unoccupied on Sept. 25 with its sails set. His body was spotted a week later near Solomons, Md., at the mouth of the Patuxent River.

Police spokesman Clark said yesterday investigators have had to "play catch up ball" while trying to find out how Paisley died because nearly all the evidence in the case has been "contaminated."

"What evidence might have been on the boat has been lost because the Coast Guard, the CIA and other people moved things around before we got there," Clark said.

The bloated, badly decomposed condition of Paisley's body" removed any evidence that might have been on the body," Clark said.

Because the bullet that killed Paisler fragmented upon impact with his skull, he said, ballistic technicians needed a week to pieace together fragments and determine that the bullet came from a 9mm cartridge,.

Clark said that "several people have told police Paisley kept a pistol aboard his sloop. No one has said they are sure the gun was on board when Paisley disappeared. Clark said.

Retired Air Force Col. Normal Wilson, a close friend of Paisley's who rented him dock space near Solomons where he moored his boat, said he had last seen the gun last atumn. Both Wilson and Myers said the gun was partly disassembled and stored in a watertight plastic bag when they last saw it.

Clark said evidence "contiminated" in the investigation included Paisleys apartment at 1500 Massachusetts Ave.

CIA officers and Maryann Paisley, "Things had been removed from the where Paisley moved this spring, apartment.It had been cleaned out," Clark said.

Paisley's retranged wife, entered the apartment before Maryland police got there, Clark said.

Clark said that one of the only "tangible things" police have found belts weighing 38 pounds taken from in their investigation is the two diving belts weighing 38 pounds taken from around Paisley's body. He said police are trying to trace ownership of the belts.

Paisley, according to family and friends, including Myers, owned only one weight belt for scuba diving. "He kept the one belt on the boat because it was too heavy to carry back and forth to his apartment," Myers said.

Myers said yesterday that as a psychiatric social worker, trained to sense people's moods, she finds it hard to believe that Paisley committed suicide.

"It would shock me to learn that his death was suicide because (that would mean) there were things he wasn't sharing with me."