Three years ago, Ellen knew she could never play the role of "the other woman."
"Some of my friends had had affairs with married people, and I really didn't respect them for it," she said. "I was pretty self-righteous about the whole thing. My parents have been happily married for years, and I just didn't feel that taking part in infidelity was OK.
"Also, I'd fairly recently broken up with a boyfriend who'd been unfaithful to me, so I knew how painful it is to find out you've been lied to."
But at some fuzzy point, that personal code of ethics Ellen thought so firmly in place began to bend under pressure.
"After the trauma I went through over my ex-boyfriend, I was having trouble trusting new relationships, so I was avoiding getting too close to the men I dated," recalled the 31-year-old Orange County woman, who requested that her city not be identified. "I was dating a lot, but nobody I felt wild about. I'd been celibate for over a year.
"In a lot of ways, it was a happy and productive time for me, because I was making major strides in my career," said Ellen, a marketing consultant. "I had a lot of time and energy to devote to work; I'm probably much further ahead today, thanks to that stage I went through. But I often felt lonely."
She met the man who would shake up her golden rules at a political fund-raiser. "We started talking at a cocktail party, and he asked me if I wanted to go to dinner afterward," Ellen said. "He made no secret of the fact that he was married and had kids, so I thought, 'Oh, well, this is innocent.' But probably I was hoping that it wasn't innocent."
He began calling her, and she continued to accept his dinner invitations. "He is a very bright, articulate man," Ellen said, "and nice-looking and charming and all that stuff.
"I kept telling myself, 'So what? We just like to talk to each other; we're not doing anything immoral.' Then, on our third or fourth date, he asked me if I wanted to go on a business trip to San Francisco with him the next weekend.
"He never pretended that he wanted to leave his wife, and that's something I still appreciate about him. He just said he liked being with me. He was in his early 40s and had been married for 15 years and said he had never been unfaithful to his wife, which probably isn't true."
The following Friday night, Ellen boarded a plane to San Francisco. And for the next 18 months, she accompanied her lover to Hawaii, New York, Chicago and New Orleans. He dropped by her apartment at least once a week, for two or three hours per visit, bringing champagne and roses.
"He's pretty well off, which isn't important to me in my real life," Ellen said. "But with him I was playing make-believe, so that was an exciting part of the fantasy--expensive restaurants, deluxe hotels, fine wine. He was so mature and in charge. He made the other guys I'd been dating look like kids.
"After all those times I stood in judgment of my friends for having affairs, I never once felt any strong pang of guilt," Ellen admitted. "I justified my actions by telling myself, 'It's his marriage, not mine. It's his responsibility to be faithful to his wife.'
"I felt like I had it all--good conversation, good sex, fun trips and no emotional drain. But I got tired of being secretive, of lying to my family and to most of my friends."
One morning, Ellen said, she realized that she had not gone out with an "available" man in a year and a half. "My mother telephoned, and in the course of our conversation she asked, 'Are you dating anyone? You never talk about having dates anymore.'
"I hung up the phone and started crying. It occurred to me that I'd become so attached to this man that I didn't even care about meeting people who could offer me a full-time relationship. I'd pretended I was so in control, but really I was in love."
Many tears and false starts later, Ellen managed to break off the affair. "I went through horrible withdrawal," she said. "For a couple of months after making the decision not to see him anymore, I'd give in and call him at work and say, 'Come on by this evening.' It was awful."
Today Ellen is engaged to a man she began dating within weeks of the final rendezvous with her married lover.
"I'd known (her fiance) for a year, but I'd never thought twice about him," Ellen said. "Yet he's perfect for me, which goes to show how distracted I was by the wrong person. I've never told him about the affair. It just sounds so sleazy."
Ellen may have survived her affair with relatively few scars. In many cases, therapist Marge Vinolus said, single people delude themselves into thinking that a married lover will leave the spouse.
"Most of the time, that is a deception, particularly if there are children," said Vinolus, a counselor with Tustin Psychotherapy Group and former assistant director of adult outpatient psychiatry at UC Irvine.
Vinolus has interviewed more than 200 people for a book she is writing about extramarital affairs. Just 10 of those interviewed left their spouses, she said.