13. There is a change in the emotional quality of your relationship. This may be shown as your partner is unengaged or overly engaged. We all, of course go through emotional changes, like the weather. However, you may notice that your partner's attitude has changed toward you over time; they may have become more self-absorbed and less interested in you or the relationship. Often, your partner may reject your offers of affection. Your best approach here is to pay attention and be curious. —Donn Peters
14. He's extremely angry. Anger and criticism that borders on cruelty is hard to take for all of us. Your partner may treat you with rudeness or impatience. He may be more controlling and more critical than usual. You may sense an increase in the degree of unhappiness in your spouse that is difficult to understand. With some partners, you may actually see an increase in happiness as a result of being involved in an affair. —Donn Peters
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15. You notice an increase in his work or his time spent away from home. Work can be demanding. During these times of economic stress, most workplaces are demanding more and more from their employees. Workplace relationships can develop into romantic relationships simply because the amount of time spent together on a common task tends to bond people together. If your partner has trouble with boundaries, this could lead to a problem for your relationship. —Donn Peters
16. He pays an unusual amount of attention to his appearance. This would be especially telling if up until now, your partner has not shown much attention to his appearance. If your partner is having an affair, he has found a new source of love and affection. Looking good for his paramour is very important. —Donn Peters
17. He's overly defensive. Defensiveness exists for many reasons. In the past, were you able to discuss issues openly and calmly? What you are looking for here is an increase in the normal amount of defensiveness. —Donn Peters
18. His appearance has changed. Your partner, who previously dressed conservatively, is now suddenly buying designer boxer shorts and more trendy clothes. Or, your partner, who never spent much time grooming himself, is now fussy about how his hair looks and uses grooming products he's never used before. —Susanne Jorgensen
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19. His behavior has changed. Your partner, who usually avoided office parties and events, is now constantly attending them "for the sake of his career." Or, your partner suddenly takes up and becomes obsessed with a new hobby or sport that keeps him away from home. Or, your partner who usually is home for dinner every night now "works late" and takes more frequent "business trips." —Susanne Jorgensen