Why is changing your mind considered a "failing"? :-) For that matter, why does divorce have to be considered a failing? These are subjective judgements, methinks.
And hey, Forum Lurker, what about the emotional risks of same-sex pairings? From what I've seen, those can be considerable.
Not trying to be difficult, just tossing more ideas in the pot...
We incarnate here in order to live out Earthly dramas that allow us to test our favourite spiritual theories in the realms of physical limitation. Those dramas allow for every eventuality, including same-sex pairings and divorce. Sometimes it's fun, sometimes it's not. That makes for a good drama. A drama in which nothing ever goes wrong is no drama at all, and no one would be interested in paying the price of admission.
Needless to say, the Canadian government has no notion whatsoever about such matters, being occupied in playing just its own rather limited and oh-so-serious and stuffy role in the ongoing drama. Still, I much prefer it to the American government's role!