The longest Long Distance Relationship obviously could not judged from how far the distance is. The distance is measured with how big the difference of beliefs in between.
We see how the nature teaches Long Distance Relationship when the Sun and Earth are always together sharing their love even they separate as far as millions miles away.
And even all human have a great Long Distance Relationship, which is Long Distance Relationship with Him, but with beliefs and faith, He even more closer than our pulse.
At the end, there is no distance stretched further when the conviction and hearts are united. Trust to your love one and being honest and true to yourself is very important.