That's the courtly love movement of the Middle Ages, not some outgrowth of modern leftism.
Shakespeare's comedies were were full of love and romance, which typically ended in marriages. This was of course considered popular entertainment at the time and not "high art," but pre- and early modern literary expressions of love and romance weren't nearly as overwhelmingly grim as you make them out to be.
It is leftist, because leftists always make empty preaching about love, empathy, and equality.
And the art being old does not make it logical or intellectually sophisticated because Jews have been infiltrating Western society since ancient times and have spread this dumb concept to lower the intelligence of gentiles by elevating their oxytocin and lowering their testosterone.
Roosh has written many articles about the stupidity and leftism of romance:
Since we were children, we have been bombarded with propaganda that romantic love is the ultimate relationship ideal. Hollywood movies, Disney cartoons, and literary fiction all portray romantic love as an absolute necessity in any wedding union, but how much of that narrative has been a lie? Is it