I don't think she broke up the Beatles, I think there was a clash of personalities there that wasn't tied to a specific relationship. She did, however, ruin what was to be a legendary collaboration between Lennon and Chuck Berry.
She and Lennon may have been right for each other. I think they both reached a point of arrogance and self-indulgence that made them complement each other well. The difference was that Lennon was absurdly talented and Yoko, not so much.
And that's the problem with contemporary art in her style: a dearth of talent and a need for attention create an urge to do something, anything, to stand out in some way. Great art by a talented artist can take you into the artist's imagination, expanding your perspective. Mediocre art often comes off as a form of trolling because the point is not to show you a rich new point of view but merely to challenge you, to piss you off. Hence the urinal exhibited as a sculpture; the banana taped to a wall; the scrawled instructions on how to create the piece exhibited instead of the piece itself, there being often no piece at all, just a bit of manic-pixie-dream-girl vagueness. ("Hide until everyone goes home. Hide until everyone forgets you. Hide until everyone dies.") And curators and collectors all standing around telling the emperor what a lovely outfit he has on.