i'm all for relationships that aren't full retard. For instance. Jedi and Sith relationships are 99% stupid. Two fundamentally opposing ways of life. It isn't just oh "I'm a buddhist and she's a christian". It is almost better to think of it in a political sense. "I am a peace focused republic minded individual and she is a totalitarian with a pragmatic viewpoint that leads to a significant amount of violence.... violence that I am obligated to stop due to my peace making job..." I have seen a few savvy relationships. Typically started stupidly, but that's a side matter. These savvy relationships understand the reality that love does not conquer that difference of mindset. Either one must change completely or the two will see an end to the relationship. The stupid relationship has them on the battlefield supporting one another (cause we're family they scream!) in completely dumb ways. And of course there are other good ways. The Sith that weds a Jedi but as part of deception, he is pretended to be a Jedi and is using the relationship as a way to get closer and faster to information. But even then that is not long and true.
