What's your book about?

I don't know why but every time I get in a conversation with someone about me writing a book I dread them asking the most obvious question. I know what the book is about, I conceived it, mulled it over night after night, wrote it, re-wrote it and read it multiple times.

Yet I am still not good at, or comfortable with, explaining to people what its about. I freeze. It was the same when I challenged myself to write the blurb, I just couldn't do it. I think its a combination of struggling to distill the idea down in to a few lines and not wanting to give away too much of the story. I am hoping that someone down the line will help me with it because it gives me the heeby-jeebies!

In the meantime, when I get the dreaded question I just stumble and mumble a few words about war and jungles and stuff and hope they change the subject quickly.

Is this just me? Or do all new authors get the blurb-traumas?