1. He's Acting Differently.

The most obvious sign of a cheating man is that he's acting differently than the way he used to. If there are any signals, don't freak out and assume he's having an affair. But be suspicious of developments. If he's always been private, hasn't ever had the highest sex drive, or flakes out on plans, that's just who he is. It's when he starts to be that way and never was before that you should start asking questions.

2. He's Avoiding You.

If he has suddenly started coming home much later, seems to be making excuses to be out of the house, starts going away without you on the weekends, or just seems to be avoiding you, that's trouble in your relationship.

3. You're Having Less/Different Sex.

A little less than half of cheating men report having less sex with their partner. Others keep having sex so that they don't raise suspicions. So be aware of the amount of sex you're having and pay attention to the quality of the sex. Sometimes when a guy is having an affair, the quantity of sex remains the same, but it's the sex itself that changes. 4. His General Response to You Has Changed.

If he's having an affair, he may stop acting like the sweet, romantic man you fell in love with. Now he gets annoyed easily, gets critical, or picks fights. Try to figure out why he's different and what could be distracting him or making him feel guilty.

5. He Has Suddenly Become Very Private.

You have a problem of he always goes into a different room to answer calls, keeps his cell in his car or gets really private about his bills. If he stops checking his e-mail in front of you or has turned the bathroom into a phone booth it's a good sign an affair is under way.

6. He is Unreliable

If he's never where he says he's going to be, it's a sign he's lying to you about something. Everyone's plans change sometimes, but if he is consistently not where he says he will be, it's possible it's because he's with another woman.

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