Hey, I am not now in a long distance relationship but I was when my relationship began. There is no denying they are difficult and the success rate is probably less than none long distance relationships but they can work. I think it depends of course on the people involved but also on the distance and the possibility of it potentially moving forward from being long distance.
I was for five years, including two years where we were on opposite sides of the planet. We're married and living together now. Advice: Communication is key for all relationships, but this is doubly true for long-distance. If something is wrong, you have to be able to talk about it because otherwise the other person will not be able to pick up on other signs that something is wrong. Part of this is figuring out a method of communication that works for you--whether that's phone calls, video calls, or texts. Make time for each other. It's easy to get wrapped up in other things and let your relationship fall to the wayside when you can't see the person. Just because you're long-distance doesn't mean you can't still have date nights.