In my opinion, getting your nose broken is just a part of life! And, in my opinion, getting your nose broken is actually strengthening your nose!
Why?
Well, just like anything else. When I attended Shotokan Karate, the instructor used to have the male students of higher ranks stand there while he kicked them in the testicles. Why would someone do that? Well, if you are kicked in the testicles over and over again, if it happens in a real fight, do you think it will be as effective on you?
We "condition" our limbs in my current school. We partner up and bang our forearms and shins together so when we block incoming strikes, it doesn't hurt...As a result, you wind up going "all out" with your blocking, because it doesn't hurt, and at that point, even something as simple as blocking would hurt an ordinary fellow. You wouldn't even have to throw a punch at them, your blocks would do the damage!
So, getting hit in the nose sucks, but if you get hit in it enough times, if, God forbid, you ever had to defend yourself in a real life situation, you may just laugh it off as you would be unaffected by it!
I am by no means telling you to get hit in the nose on purpose! Keep your guard up and you won't get hit in the nose! I am just simply reiterating the old saying, "What doesn't kill you, only makes you stronger!"