Relationship alert: 82 percent of affairs happen with someone who was at first "just a friend," according to noted infidelity researcher Shirley P. Glass.
So... despite any obvious signs of cheating in your so-called friendship, ask yourself: Are you having an emotional affair?
You've Probably Crossed the Line if You...
1. Touch your male friend in "legal" ways, like picking lint off his blazer.
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2. Pay extra attention to how you look before you see him.
3. Think crush-like thoughts like "He'd love this song!"
4. Tell him more details about your day than you do your partner.
5. No longer feel comfortable telling your mate about this person and begin to cover up your relationship.
6. Experience increasing sensual tension; you admit your attraction to him but also insist to yourself that you would never act on it.
It's About to Get Physical When You...
1. Find yourself feeling vulnerable and turn to the other man for support rather than to your mate or a trusted relative or girlfriend.
2. Accelerate the level of intimacy through sensual or suggestive talk over email or the phone.
3. Put yourself in a situation where the two of you could be alone.
You Can Avoid the Potential Affair if You...
1. Stay honest with your partner. Share with him all your hopes, triumphs, and failures -- as well as your attractions and temptations, which will help keep you from acting on them.
2. Make time for just the two of you on a regular basis -- away from the kids, your friends, and family.
3. Surround yourself with happy couples who don't believe in fooling around. Having positive, emotionally connected role models will help you stay on track.
Readers Reveal: "I Knew I'd Gone too Far When..."
"The guy who I was flirting with regularly over email attended the same event as me and my fiance. When I introduced them, my face flushed as red as a tomato -- I felt embarrassed and guilty about my fiance meeting this guy, so I knew what I was doing was wrong." -- Carolyn, 31, Westfield, NJ
"During one night of partying, my best guy friend and I confessed we had always liked each other. He was a perfect gentleman and left my place before we crossed the physical line. The next day I was completely embarrassed and knew that I didn't want to jeopardize the relationship with my boyfriend so I ended the friendship. And now the boyfriend is my husband, so I'm glad I did." -- Allie, 29, Yonkers, NY
"The cute tech guy who I'd been flirting with at my office said to me, 'You're not going to invite me in?' after I accepted a ride home from him. I liked the attention of him buying me vending machine snacks and complimenting me, but my husband would've had a heart attack if he knew." -- Amy, 38, Chicago
"My best guy friend and I were snuggled on his couch underneath a blanket when I realized that neither his girlfriend nor my boyfriend would be happy if they saw us -- and that our platonic relationship wasn't as platonic as we thought." -- Kim, 35, New Orleans[b]