I don't want my bfs brother to be part of his life
Why are you trying to come between him and his brother?
Do you know what a nuisance he is?
I see how that may affect how you feel about him, and make it hard to include him. That being said your boyfriend can have his family in his life if he wants.
No way. I will not let that happen.
That is going to cause some issues in your relationship if you act that way. It is not okay to try to put a wedge between your BF and their family.