You cannot win on an individual level with someone who does not play by any rules, who has no morals and who delights in dominating and winding up other people.....
very very true, indie.
Sadly, it is also true that if you have never had close contact with this type of person, then the sideline viewers tend to think "well, they're as bad as each other".
And the lovely line taken by M Obama of "they go low, we go high" ....well, that ends up in a situation where the abuser/narcissist "wins".
Unfortunately, for those same sideline viewers, the abuser will never have satisfaction from their "win" and will always look for a new target. So, while you may not be in the firing line right now, at some point the abuser/narcissist will impinge on you.
For someone of Martina's wisdom and strength, engagement is probably not the best option. There is no persuading, no logic, no argument that will open the mind of an abuser.