I truly hope that your family will come around to the realization that you did what they could not or would not do to HELP your brother and the ones he hurt. I am dealing with an alcoholic,bipolar,psycotic, sister right now who is hurting her grown children. I can't protect them anymore but I did what I had to do when they were younger and was at odds with my mother quite often. Listen to your inner voice and you will find peace in your actions regardless of what others will say.
My love and hugs go out to you in your time of turmoil.
I wish I had more to offer but what I am feeling can not be put into words. Just know I am with you and so is your higher power.