I am going through the same thing. Except I am violent towards my boyfriend. I actually hit him so hard I jammed my finger. At that point, I knew I had to get help.
I have been told the best way to deal with my anger issues is to talk to someone.
This may be a silly question, but are you happy enough with your significant other to make the move, and so you are scared and lashing out in anger because you aren't sure it is the right move?