Many women - and men – say that infidelity is the one thing they will not tolerate from their spouses.Until it happens, that is. Many marriages sink under the weight of infidelity, but many more survive. So how do you tell if your spouse is unfaithful?Jealousy can make you very nastyUnless you have a history of unhealthy obsessional and jealous behaviour, chances are that if you suspect that your spouse is having an affair, you could be right.It is important to remember that you need to look for a pattern in your spouse’s behaviour, not a one-off incident.Coming home from work an hour late once means nothing, but it does take on a certain sinister undertone when it happens for the third time in one week.But before you get out your boxing gloves and hire a private detective, just listen to the explanation. If he/she is an accountant and the financial year-end is a week away, working overtime is quite plausible.If you expect your spouse to account for every minute of their day and fly into a jealous rage if they can’t, you might be the one with a serious problem and who needs help fast.Shouting at your wife because she is ten minutes late from the supermarket is not normal behaviour and will serve to alienate her. No-one wants to feel imprisoned.What are the signs of cheating?* He/she receives phonecalls that they don’t want you to overhear. * He/she has an e-mail address to which you do not have access. * You get the impression that you are often lied to about little things. * You no longer seem to have serious and intelligent conversations about important things and you get the feeling that your company is being avoided. * Your spouse spends hours and hours in on-line chatrooms. * Your spouse has more and more unaccounted time away from home. * You discover your spouse has a post office box, which you did not know about. * The passenger seat in the car has been moved from its usual position. * Often when you answer the phone, the caller hangs up on the other side. * Your spouse has a separate bank account you did not know about. * There are credit card transactions for gifts, hotels and restaurants that you cannot recall. * There is a sudden increase in your phone bill. * Your spouse suddenly looks different – new clothes, new hairstyle. * Your spouse suddenly has a decreased interest in having sex with you. * Your spouse joins the gym after years of being a slothful couch potato. * His/her cellphone is often switched off when you are trying to get into contact. * Your spouse is particularly attentive or particularly inattentive towards you. * You press the redial button on the phone and get through to someone you don’t know. * Your spouse tries to pick fights with you so that he/she can storm out of the house and disappear for a few hours. * When you raise your concerns, you are told that you are excessively paranoid.Just on a cautionary note – these are merely signs that shouldn’t be missed, but are very far from real proof.To get that, you might need to either follow him/her or confront them directly. Who knows, you might even get an honest answer.You don’t really want to be the last person to find out, do you?