If you are just tinkering with the idea that your partner may be cheating on you then be aware you are walking on very thin ice unless you can prove he or she is cheating and that can be difficult to do. If you really feel they are then it would be a good idea to interview private detectives; choose one to follow your partner and it should only take the private detective a couple of weeks to find out if your partner is cheating. If they is not then be smart and don't let them know about the detective, but learn from that experience and start trusting your partner and start to learn how to communicate with them.