The clearest sign that your partner is cheating involve changes in their behavior, such as changes in their normal routine and changes in how they do or don't express their affection for you.
There are visual, physical and intuitive signs. The visual include lipstick on the collar, changes in your partner's appearance and habit while the physical include emails, text messages, phone bills and the intuitive are your instincts that tell you something is not right. In the case of any of these, it is important that you listen to your senses and instincts. Most people will not act on the first indicator as we give others the benefit of the doubt. But, once the signs pass the "tipping point" it is important that you talk to your partner.
The author of Intimacy after Infidelity: How to Rebuild and Affair-Proof Your Marriage (2007, New Harbinger Publications), Dr. Solomon received his undergraduate degree at Dartmouth College and his M.A. and Ph.D. in Clinical Psychology at the California School of Professional Psychology (Los Angeles). He has been in private practice in San Diego and La Jolla, California for more than 20 years.