If you think your spouse is cheating then likely your suspicions are right. Hiring a private investigator can put your worries at ease or in the event he or she is cheating, you will have to decide what to do with the information. If divorce is a consideration, proof of adultery is highly significant. Legally, one shows evidence of adultery if there is an indication of more than a friendship (like hugging and kissing) and there is opportunity (like they spend the night together). I would not have to place a camera in their bedroom to prove adultery.