Sometimes, people just fall apart for no reason. Sometimes, its the biggest fiasco in the world that leads to the destruction of what once was the most beautiful thing on Earth. Oftentimes though, people are not able to really pinpoint why they drifted away, fell out of love, or just took different paths from each other ... from someone the they vowed to love for the rest of their life or till the day they die.
I think its because where before happiness trumped any sadness or pain that someone brings in your life, now its the complete opposite. I believe that we drift away when we no longer feel as happy as we used to, when the sadness overtakes us, and the pain becomes too much to bear.
When this happens ... sometimes, even when we don't want to, it's time to say goodbye.