You are right in associating the abuse by your mother's boyfriend to Depression and anxiety. A person can be adversely affected and in an ongoing manner when they don't realize this. You only need to realize that the fear is due to a threat made through the abuse of relationship and thus any associated ideas are just suggestions, the hater's bullsh*t. Knowing this you can discharge the ideas, which means you are home free. The Depression and anxiety can't be created when you know that the ideas are false.