Not true...CAmilla married another man first...THEN Charles found Diana....who had various mental disturbances pretty much from the get go.
Camilla only married another man when she knew that waiting around for Charles was a lost cause; however, neither ever fell out of love with the other. It was Charles’ father who did everything humanly possible ( like having Charles sent away on extended,supposedly “needed” trips and then forbidding that marriage )to kibosh that relationship and then forced his aging son to marry the execrable Diana.