What line of work is OM in?

It's better to expose him with management than with his friends... It all depends on the line of work he's in...

Get his parent's contact numbers if you know them at all... They may do nothing, but he will be humiliated that you went that route...

Part of the thing by exposing to his parents is that he realizes HE is vulnerable too and that YOU will take the offense if he isnt' backing down...

If you just keep playing defense with OM he is NOT going to leave anytime soon.. He has to realize he has something you can TAKE AWAY from him.

He has to realize you can "bring rain" down on him too as QS likes to say...

Additional work will come later, including surveilance for both your W and OM