Me and my acute inability of letting things go...

Why is it that I, almost always, have problem letting things go. I have found myself being illogical many of the times, and often face this issue. One of the reasons may be that, by character I am a person who never accepts things as it, I always try to challenge the status quo and try to see if there is any scope to make things better. When people say "it can't be done" or "it cannot happen", I ask "Why" or "why not". Strangely enough most of the times, they answer "do not know why, but it can't be done", and this particularly irritates me very much. This attitude of mine is quite logical, but this characteristic often interferes in things where I become too stubborn to accept the things, move ahead and have peace in life.

Well I am not sure if this is ok or not, but I am keeping this post open to addition as days go by...