Are you alone?

Have you ever felt alone? Of course you have, but thats not what I mean. I mean, when you have everything, but still you don't feel right. You have great friends, a girlfriend, parents etc. but still you feel alone. Why is that? This feeling of misunderstanding? Its like you are happy, but at the same time you live in a totally different reality where you are and feel lonely. Weird, isn't it?