No, that's not a silly question. In fact i was just reading an article about that last night in my psychology today magizine. I think it is the fact that people have emotions, and we take out our frustrations on the ones we love the most. However, unlike your parents, we can pick our mates. Also, we are searching for something that we don't even know what it looks like. (true happiness) I have found that it helps to look at the good things in life and give people the benifet of the doubt. (which for me is hard to do and i'm still trying to figure that out completly) but when i do do it, it seems to work.