Bad Bosses - They are a fact of life in the working environment. If you've not experienced one yet, you have been lucky.
One of the first bits of advice I was given about a bad boss was not to let it get to you. I know this is hard, but try a model of "It's you not me" thats the problem. As a graduate you will rotate quickly and should always be looking for new opportunities. So consider the bad boss a short term thing.
Don't hold it against the company too, often its the person thats the issue not the company per se so keep an open mind about the whole organisation.