... that this is a real world relationship, the first thought that came to my mind was that old adage about the grass always being greener on the other side.
As we seem to take our baggage with us when we go, it may end up to be same shit, different patch of grass.
Having said that, I also think if you are not satisfied to a reasonable degree with the current relationship and you've tried your best, then move on. Life is a series of lessons and the only way to learn is to take the leap into the unknown. At least you won't be laying on your deathbed thinking about all the things you wished you'd done.
(feeling rather verbose today - pardon me!)