Last night I had a dream that I was given the task to destroy a nest of vampires. I was given a banana as the tool, and my techer assured me it would do the trick. He explained in length how I was to stab the vampire through the heart with the banana. I went into the nest of vampires who were in a suspended animation of sorts. There was a family. Believing the banana would not work, I chose a small child as my first victim, feeling I would have a better chance of escape. I desperately mashed the banana against his chest, and as expected I was sitting there like a fool maching a banana against the chest of a vampire child as his parents looked on. It was at this point the suspened animation ended. I then thought - guess I should run now. I was never afraid, only calculating. I knew it was time to run so I ran. Like a video game that you have played over and over again, where you know what is going to happen. The vampires were flying around in a tissy like wasps when you knock their nest down, but they never got me - It was like I knew the possitions I needed to be in for them not to 'see' me. There was a second part to the dream, after the escape, but I canot remember it.

Your dream of the vampires sounds as if you are in real life surrounded by the wrong people. Even the teacher, represents a friend you trust more than the others, and he gave you bad advice in the dream.
It could be his advice was not only bad for ridding yourself of the wrong people. Or this person is putting these things in your head, that these people are not right for you. And his tool the banana, does not work, because the question is: "Are the vampires really the problem? or is that close friend the problem?" The family element can mean friends, who seem as family.

I would say its time to clean house, and get rid of friendships or relationships that are draining you, like a 'vampire would.'