I am sure you all know a human bulldozer in your life. That person who's "telling it like it is" , that person who will tell you "that's just the way he/she is" and who will think you're a weakling if you even dare question their way of expressing themselves.
I have to admit I am completely baffled by this attitude. There is blunt and then there is "so blunt a dozen of bulldozers charging at you full speed feel like you've been touched by a feather" blunt.
Remember not everyone is like you. Just because someone does not like what you have to say or how you say it does not make them weak, it just makes them human and different from you.
With that said, that doesn't mean you should NEVER say anything! When something bothers you, please speak up. Don't let a problem linger until you can't take it anymore and blow up. You may be afraid of the other person's reaction, but if you wait wait wait and wait some more, it will only make things worse.
Best wishes and good luck :)