A relationship is a connection emotionally, physically and materially between two or more people. When those two people are in the same place, it's much easier to maintain the relationship , but when the distance comes in, things get complicated. I believe that a long distance relationship is it's a tough thing to do , for a numer of reasons.
Firstly , feelings are hard to express at a distance. The essence of the idea of relationship is lost and people are not having the opportunity to make memories.
Secondly , being separated, partners are attracted to other temptations and I can put it in danger the relationship. Lack of limits and lack of supervision urges people to deceive trust and change plans.
Admittedly , If there is full confidence and love, I do not think there should be any problems. However , our mind can overthink anything.
In conclusion , according to the arguments presented i believe that a long distance relationship is  a difficult thing to live.