With their marriage officially on the rocks, Heidi Montag and Spencer Pratt are now accusing each other of infidelity, with Montag even going so far as to hire a private investigator, according to Radar Online. “She is very anxious to find out if her suspicions and the rumors are true, especially if he’s spent any money on another woman,” a source says. “Heidi has hired a former member of the sheriff’s department, who now works as a private investigator, to look into it. It is really important to Heidi to find out if Spencer has been cheating on her.”