This randomly came to me a minute ago talking to somebody, and I just HAVE to write it all out because It's fresh now and it's interesting.
What my main point is here (and I will start with it) is that for a couple to last, they two partners must not change. This is why highschool relationships fail, because at a younger age as a person your undergoing a lot of new ideas and concepts, and its only a short amount of time before you're a completely different person than you were before. Now the idea is that for a couple to last, they must grow/change together. So possibly 100s of years ago this could work at a younger age as there was less complexions involved, such as moving away for education, or parenting methods, etc.
Anyways so that all down, back to the bigger part, why divorce rates are rising. So obviously everyone's great grandparents are still together, and also everyone's parents are separated. And by everyone I mean general majority. Either way, only a fool would try to argue otherwise regardless of if you fall into that category. So the only possible cause with substantial effect on this is the fact that the two partners get bored of each other, or they each go their own path. So why didn't this happen in earlier years? Well the answer is simple, the only thing now that wasn't before is technology. With all sorts of new communication methods availible, TV, internet, music, etc. Each partner is introduced to hundreds of outside influences that the other is NOT. As a result, this slowly changes the person and causes the inevitable separation to occur.