Edna Cruikshank was married in Cambridge, Mass., in a the same small Catholic church where her mother and grandmother had been married. "My mother's maiden name was Doyle, and she married a Doyle," she says. "I am very Irish."

For 20 years she has lived in the same Alexandria apartment building. She worked for most of those years--recently as a manager of a dress store. "I slowed down about two years ago," she says. At 60, she is thinking of retiring in the south.

"The way to a happy marriage is to get as far away as possible from both of your in- laws," she says. "Just visit. That's the advice I gave Peter and Carol."

With bright blue eyes and a thick shock of red hair, she is a spirited woman--proud, feisty and independent.

For years she had her own motorboat and was a member of the National Potomac Yacht Club. "I was the first woman vice commodore there," she says. "I just love the water--the tranquillity of water. Swaying in the water is like being in your mother's womb again. In this family we are a boating people."

She says the Cruikshanks are a stubborn bunch--except for Peter, whom she describes as "a beautiful crutch for me."

"I am the black sheep of the family," she says with a wink. "I was a churchgoing woman. But now I don't go. Not till I am ready to go on my own. Some day. Oh, I went when my brother-in-law died. But I don't go regularly--the way I used to. My sister, nieces and grandchildren all go to church regularly."

The major trauma in Cruikshank's life was when she and her husband separated, leaving her with three children to raise. Since 1969, when he returned from Vietnam after working for the State Department, Ralph Cruikshank Sr. has cut off all contact with his family here.

"He was a very proud, beautiful person," Edna Cruikshank says, "a family man. He was a good officer--became a lieutenant colonel from buck private. Then, all of a sudden, it happened."

The Cruikshanks never got a divorce.

"I don't believe in divorce," she says. "I was taught that marriages are made in heaven. I believe God united us.

"I have been let down by the church, but I still believe. The Man Upstairs and I speak a lot. I don't have to go to a house of prayer to speak to Him. I don't need intermediaries."

Cruikshank is "just delighted" withPeter's "good fortune in finding Carol," and she predicts that their marriage will be "very firm."

"I think the world of Carol," she says. "Peter was in complete disarray when his first marriage broke up. He lived here, in my apartment, was in and out. His children come here all the time, and when his former wife's new baby was born, I sent a gift. There is too much bitterness in this world. I can't hate. I am glad that Peter and Liz found out early enough that they can start again."