I've been 'in relationships' long-distance, but they've all been superficial and ended up with both me and the other partner drifting our separate ways.
It helps that I'm poly-friendly and don't mind if they're seeing other people on the side. Being that I'm kind of distant from people anyhow, they usually end up with stronger emotional ties to the other person, and eventually the connection between the two of us dries up.
I'm not bitter or angry about any of that, though. ... When in a relationship, generally all I want is for the other person to be happy. If it's happiness with another person that they find, then so be it.
This also might explain why all of my previous relationships have ended in a similar way. >.>