If you suspect that your boyfriend is cheating, the best thing to do is to find out for sure. The likely culprit is a woman he is familiar with. By observing how he relates to other women and how they relate to him you can tell whether or not he is cheating.
Another way is by looking for tangible evidence. This can be done by going through his car trunk, glove compartment, his wallet, pockets, backpack/ briefcase, the drawers or any other place you could think of where he may have left evidence.
Another skillful tactic to employ is to utilize surprise visits especially on evenings when he says he is working late or on random lunch hours. You could drop by with a meal or an invite to one then study his reaction to see if you can decipher anxiety. On evenings when he is working late, if he is not in the office then something is amiss.
Finances also give large tip offs. His credit card bill could contain purchases and gifts that are of a feminine nature that you did not receive. They could also have restaurant or hotel visits that are out of place. The gas bill can also prove to be very insightful especially if your boyfriend fuelled his car at a location that is out of his way and that he shouldn't have been at.
Using spy ware to see the emails he sends and the chat sessions that he has could also help with catching your boyfriend cheating. This spy ware can be installed in his computer undetected and the surveillance can take place from your computer. You can also keep tabs on his phone by employing phone lock up to find out the owner of any mysterious number that calls him.
If indeed you do catch your boyfriend cheating, you should be calm about it despite the inner raging storm and endeavor to move on. No cheat is worth the trouble and should the relationship completely disintegrate then be positive and outgoing and another great romance is likely to come your way.