Truth: men cheat more often than women and cheating is always about sex.

Infidelity is a common phenomenon, and has touched most of our lives in one way or the other.

Read on for the top 12 infidelity myths and the truth -- or lack thereof -- behind them.

Myth No. 1: People cheat because they're unhappy at home

If you're female, this is usually the case. Women in long-term marriages who are having affairs report low satisfaction with their marriage. For men, on the other hand, that's not necessarily the case. Many men who love their partners and have great sex at home never turn down an opportunity for a bit on the side if they think they can get away with it. In one study, 56% of cheating men surveyed said their marriages were very happy. Only 34% of unfaithful women agreed.

Myth No. 2: Men cheat much more than women do

This used to be the case, but now the infidelity scales are balancing out. Why? Women cheat for the same reasons as men: It's someone new. It's naughty (and therefore nice). However, there are other reasons women cite: The affair was a "reward" for being an unappreciated wife and mother or for putting up with a partner who wasn't affectionate, didn't listen or ignored them. It was an "ego boost." (Gone are the days when we'd treat ourselves to a new lipstick or haircut to cheer ourselves up.) We're still not as blase about affairs as men -- women are more likely to feel guilty -- but given that studies show we're much better at lying, we're also more likely to get away with it.

Myth No. 3: Affairs are mostly about sex

Some affairs are about sex and most certainly include sex because sex with someone else is forbidden, making it very appealing. However, sex is not always the reason people cheat. Affairs are a way for people to get something they're not getting from the relationship they're in -- it's that simple. What's not so simple is defining what it is that's missing. In fact, oftentimes the cheating partner isn't aware of it. Some people are searching for something they lost as a child, others for lost youth. Some people cheat on "perfect" partners because they're sick of perfection. It's not always about sex.

Myth No. 4: If she cheats on you, she doesn't love you

It may feel that way, but it's not necessarily the case. It does, however, mean that your partner doesn't respect you enough to honor the commitment you've made to one another and that he has a different value system than yours. Some people are more than capable of separating sex from love and physically sleeping with someone else doesn't affect their love for you.

Myth No. 5: Sex with an ex isn't cheating because you've been there, done that

Sleeping with an ex is the sexual slip-up people most commonly expect to get away with. It doesn't feel like you're being unfaithful -- it's not as if it's with someone new who might expect the sex to turn into a relationship -- right? Wrong. Sadly, this is exactly why sex with an ex can have disastrous consequences. You might be having a shag for old times' sake, but your ex may be doing it as a desperate bid to rekindle the relationship. So you have to break it off (again) and explain to your current partner why you're suddenly getting e-mails or calls from him after all this time. The chances of getting found out are actually higher than if you'd had sex with a stranger because strangers won't feel the need to write a long, incriminating closure e-mail.

Myth No. 6: You can affair-proof your relationship

You can lower the chances of an affair in your relationship, but there are never any guarantees. The next best thing? Choose the right partner. Choosing the right person is more important than keeping them happy once you've got them because things like morals, values systems and family backgrounds are much stronger influences on whether someone will cheat (or not).

Myth No. 7: If she has a history of cheating, she'll probably cheat on you too

This one is almost always true. If your partner's cheated on almost everyone they've been out with -- and nothing has happened to make them rethink their behavior -- they'll almost certainly do the same to you.

Myth No. 8: You should always confess if you've had an affair

If the affair is known or strongly suspected, you're better off telling. You've got more chance of rescuing your relationship after a voluntary confession than after an unwanted discovery. However, if it's unlikely to be discovered, there are also valid reasons for keeping your mouth shut. For example, some experts will advise you not to tell if your partner's not the strongest person emotionally. News of an affair isn't exactly going to give them a leg up on that steep, bumpy road to high self-esteem. Telling is going to wipe out any trust they'd mustered up, and it could take years to rebuild (if, indeed, that's possible). Instead, work out why you had the affair in the first place. What were you getting from it that you aren't getting from the relationship you're in? Is it possible to create that with the person you're already with?

The worst possible reason to confess an affair is to make yourself feel better. True, it will lift the guilt off your shoulders, but it will plonk a whole heap of pain on your partner's. You made the mistake, now deal with the consequences.

Myth No. 9: Cheating doesn't count if no one finds out about it

Does cheating really matter if there's absolutely no chance you'd ever get found out, you will never see the person again, you had safe sex, it meant nothing, and you told no one? It completely depends on your personality. If you genuinely see nothing wrong with what you did, it probably doesn't. There's just one problem with this theory: Very few people truly believe there's nothing wrong with cheating. Even dodgy people are aware they're doing something "wrong" and this is where it all unravels, as your perception of your partner changes. You're one up on him because you got away with something. This makes him appear either naive and too trusting, or vulnerable and hopelessly helpless. Good relationships are based on mutual admiration and respect, not pitying your partner or secretly thinking they're ignorant.

Myth No. 10: If there's no sex involved, it's not an affair

Emotional infidelity -- deep, passionate connections between people who often aren't even aware they've crossed the line from platonic friendship to romantic love -- is the biggest threat a marriage can face. More than 80% of unfaithful people have affairs with someone who'd started out as "just a friend," very often a workmate. In fact, one study showed that 50% of unfaithful women and 62% of unfaithful men were involved with someone at work. Intense but invisible, erotic but unconsumed, emotional infidelity is dangerous, addictive and way too easy to get away with. If you're often pretending you're single when you're not; if you send secret texts or e-mails; if you share intimate details of your life with people you fancy and lie to your partner about seeing them, you're an emotional cheater.

Myth No. 11: Fantasizing about someone else means you're about to be unfaithful

While many sex therapists will actually encourage couples in long-term relationships to fantasize about other people to cope with temptation -- logic being, it's OK to be unfaithful in your head, just not your bed -- others say it's risky. They say affairs start in the mind and fantasy sex can make you want the real thing even more. The whole point of fantasies, after all, is to conjure up brilliantly perfect sex. While the real-life unfaithful encounter is likely to be far less exciting and imperfect, strong images can increase the craving to stray.

Myth No. 12: Affairs can "save" relationships

This is a myth perpetuated by cheating people as justification for what they've done. And it's false. Can you imagine a couple ever saying, "Boy, that affair was the best thing to ever happen to us"? That's because you won't. Affairs usually involve breaking a vow, lying on a regular basis and betraying trust. Even those who survive find the relationship tinged with resentment, sadness and guilt.

Having said that, looking at the reasons why the person strayed can help piece together what's left of what you had before. People often have affairs to reinvent themselves or, more accurately, to be the person they think they want to be. A long-term partner is likely to see you as the person you were when you met, rather than the person you've become, or the person you want to become. An affair gives you the chance to start over. That's why, after an affair, it's important to ask, "Who were you with that person? How can you be that person with me?"

(Source: iVillage syndication)