it is time consuming and overwhelming in a relationship. you have to start to live according to each others schedules. things get topsy turvy, and you have to be there emotionally for another, and if you have your own emotional problems it gets very hard to deal with anothers beside yourself. i think sometimes people just get bored with another too. people have to keep on top of things and do differrent things that each other like, maybe not even liking what the other likes, that is why people should have alot in common as to activities etc..