If you like the instructor I would try and continue with it. I don't give a rat's you know what about what other people think.

I have my grandpa's pug in agility right now, and there are a few people who I don't particularily get along with in the class. I just stay away from them.

If you and Nebo are having fun (this experience excluded) I would try and stick with it. Do talk to the instructor though and see what she says. She sounds like she's willing to stick up for you and Nebo.

Good luck and I hope everything works out okay.