How to stop fear-aggresion/?

With respect, I would encourage you to read a couple of books, or watch some videos on raising and training dogs. Watch for the name Cesar Millan, "The Dog Whisperer" who also has a TV show on the National Geographic channel. Another good program is on Animal Planet, called "It's me or the Dog," with Victoria Stillwell. Both programs are very instructive and often deal with issues you mention. Best wishes.