Before you even consider investigating further, bear in mind that whether your suspicions are right or wrong, sneaking around behind your partner’s back is going to exacerbate any problems the two of you already have. If there’s nothing going on and your partner finds out you’ve been looking for evidence they’re likely to resent your lack of trust. Even if there is something going on, you’re still invading your partner’s privacy and while you might feel the invasion is justified, the anger it will cause will make dealing with the affair itself even harder.
Consider what would happen if you just approached your partner calmly and honestly and broached the subject. If there’s nothing going on then you’ve shown that you trust them by not rushing headlong into evidence-gathering. If there is something going on, there’s a good chance your partner will admit it, given the opportunity to unburden themselves. If they don’t and they are having an affair, you still have the option of investigating further in the future if you still have suspicions.
It’s also important to ask yourself why you’re suspicious. Do you have any real reason to think that your partner’s having an affair, or is it just that you feel your relationship is lacking something – perhaps the excitement it used to – and you’re looking for something outside the relationship to blame?
Past infidelities or traumas can sometimes make people misread situations, becoming suspicious for no reason and all but eliminating the ‘benefit of the doubt’ most of us naturally give our partners. Many of the ‘classic’ signs that someone’s having an affair can have alternate explanations: if your partner suddenly starts dressing better or gets a new haircut, would you assume it’s to impress a new secret love or to impress you? Do long hours at the office instantly scream to you that your partner’s indulging in an office romance, or simply that they’re serious (maybe too serious) about their career? This is another reason why a constructive, honest conversation with your partner about how your relationship’s going is usually a good move: it’ll give you both the chance to identify and work out any problems, whether they involve an affair or not. If you feel your partner is spending too much time at the office and are starting to resent seeing so little of them, say that rather than assuming it’s an indicator of an affair. If your partner is having an affair, it’ll likely come out in the conversation anyway. You’ve got nothing to lose – why not try it?
None of this is to say that you shouldn’t act on your suspicions or that it’s okay for your partner to cheat on you. But it is important to eliminate all the other possibilities first before you take an irrevocable step. As soon as you start opening briefcases or examining cell phones, you become the accuser, the enemy. Plenty of relationships are damaged by people having affairs, but plenty are also damaged by unfounded suspicions.
If you’ve had the conversation and your suspicions still aren’t allayed, you might find these articles on cell phone signs of an affair and email, bank record and behavioral signs of an affair useful.