#1 - the BP is more scared of u and thinks u are a threat.
#2 - if u are scared of your BP and always back away when it strikes, it will be trained/conditioned to think that the aggressive behavior is acceptable. so it will always hiss or strike at u. it will associate it's aggression with being left alone.
#3 - you have to step up, find a routine to handle it until it becomes calmer and knows that you are not a threat.