Sorry wish I could narrow dates better.  Somewhere between late 80s and early 2000s.  Plot is late twentys/early 30’s couple about to be married.  Friend from college is coming to visit for weekend to congratulate them.  Seems the visiting guy was really more her friend/possible ex/or wannabe then his. Visitor shows up but has his really attractive girlfriend in tow–he is not real attractive.  Go thru the visiting and such where the visiting guy is obviously paying more attention to female fiance than anything else. Later in evening couples get seperated.  It is just the male fiance and the vistors girlfriend hanging out talking obviously forming a bond.  They fool around.   The wedding get called off.   Guy fiance tries to find the girl later and finds out she wasn’t the visiting guys girlfriend.  That she had been paid to show up with visiting guy and seduce him to breakup the marriage because visiting guy wanted the woman fiance.  This has been driving me crazy for years.  Hope someone has a suggestion.