Sometimes, when the going gets tough, the tough get it on with someone else. But what really makes men stray? A nagging girlfriend? Bad sex? An escape from loneliness? Yes, yes and yes. Hear why these men slipped away from their girlfriends and landed in someone else’s bed. Then — whether you’re a guy or a girl — use the info below to sidestep this kind of situation in your love life.

Reason #1: For payback
“I once cheated on my girlfriend after I saw on her cell phone that she had been text-messaging with her ex. They were pretty harmless messages, but it angered me that she had been communicating with him in the first place — I’d always thought they were a little too chummy. That night, I was out with friends and had a lot to drink. I got so worked up about those messages that I pretty much made it my mission to find another girl and hook up with her, which I did. I think it was a payback thing. We eventually broke up, but not because of that incident — I never told her — but more so because we just weren’t right for each other. I know it wasn’t the best way to handle my anger, but at the time, it sure did feel good.”
— Christopher, 29, Oakland, CA

Reason #2: The physical attraction just isn’t there
“Ever since I can remember, I have always been attracted to women with large chests. My ex-girlfriend was great in a lot of ways, but she was completely flat-chested, which did absolutely nothing to make me sexually attracted to her. I tried to look past it, but it was hard. About two months into our relationship, I was out with a bunch of friends at a sports bar, and our incredibly hot and ample-chested waitress was really hitting on me. She gave me her number and asked me if I wanted me to meet her after her shift was over. I agreed, and ended up sleeping with her. It was just a one night thing, but it helped me realize I needed to end things with my girlfriend, because I had to be with someone I was madly attracted to.”
— Dave, 26, Roanoke, VA

Reason #3: She just isn’t there
“I cheated on my ex at a time when she was traveling so much that I never saw her. It was almost as if I didn’t have a girlfriend. I got so lonely — especially on the weekend nights, and I missed that companionship, both physically and emotionally. When she was gone, I began seeing someone else while I was still technically seeing my ex. I ended up telling my ex and she broke it off with me. In the end, I think things ended for the better, even though the steps I took to make it happen weren’t very honorable. I now make sure that whoever I choose to date doesn’t have a job that requires big-time traveling.”
— Scott, 30, Jessup, MD

Reason #4: He thinks he’s missing out
“I had dated Melanie all through college ever since we met at orientation. After we graduated, I moved to New York and she moved to Chicago, but we decided we’d stay together. I spent nearly every weekend traveling to see her, but during the week, I’d go out with my friends in New York and have a blast. After a few months of that drill, I knew staying true to her would be tough; going out in the city made me realize how many smart, beautiful women are out there, and never having been with anyone other than Melanie made me feel like I was missing out on a lot of fun. One night I hooked up with another girl, which finally made me realize I had to end things with Melanie. I told her what happened, and, as it turned out, she had done the same thing a few times. While we were both hurt, we realized we needed to take some time off. We stayed friends, and still are today, even though we’re married to different people.”
— Tom, 35, New York, NY

Reason #5: He’s moved on emotionally
“I met my ex in a Weight Watchers meeting, of all places. When we started dating, we were both about 50 pounds overweight. As the months went by, I took the program really seriously and quickly dropped weight. She didn’t adhere to the program, and her weight didn’t come off. After I lost the weight, I felt this new sense of confidence — women who had never spoken to me before began approaching me, and it felt great. My ex, on the other hand, was depressed about being heavy, and was always jealous of other women. One weekend when she was out of town, I met this gorgeous woman at my gym and we slept together. I never told my ex, but I did end up breaking up with her a few weeks after that incident. I’ve realized since then that I need to be with women who are on the same page as me about the things in my life that are important.”
— Brad, 41, Houston, TX

Reason #6: There’s too much fighting
“My ex and I used to live together, and we fought all the time. The constant tension made me miserable. In contrast to my ex, there was a girl at work who was easygoing, friendly and fun. One night we were both working late and ended up getting a drink together after we left. One thing led to another, and I ended up staying over at her place. As bad as this may sound, after that happened, I felt free. It was as if I finally had the courage to just end it with my ex already. When I came home the next morning, my ex went crazy, but for the first time, it didn’t bother me, because I knew what I was going to do. I told her exactly what had happened and that I’d be moving out that week, and I did. I began seeing the girl from work, and we’ve been together for about four months now.”
— Nate, 34, Boulder, CO

Reason #7: He needs a shot of self-esteem
“I’m really shy, and have never felt very comfortable approaching women. I once had a girlfriend who was just as shy as me. Our relationship was fine — nothing too exciting — but I was resigned to the fact that it was my best option. I went to a conference for business, and during one of the dinners, a really attractive, sexy woman at my table began hitting on me like mad. I was so shocked; nothing like that had ever happened to me before. It made my self-confidence skyrocket, and I felt on top of the world. She and I were together that night and a few other times during the conference. I never told my ex about what had happened, but I did end things with her a few months later. After the conference the other woman and I never saw each other again, but the experience gave me the confidence that I could go out and approach interesting, exciting women — I just needed that push.”
— Charlie, 33, St. Louis, MO

Reason #8: To fulfill a fantasy
“I once cheated on my girlfriend of six months when a girl I had been pining over for quite some time came on to me. She had been with someone else for a long time, so I knew she was off-limits. I have to admit, I’d still probably do it again; it was like my fantasy finally came true. I broke up with my girlfriend and dated this girl for a while, but we didn’t last. Sometimes, the fantasy is better than the reality!”
— Mark, 44, New York, NY