You get two kinds of fear: I guess you could call them "trivial fear" and "existential fear". Trivial fear is the kind of anxiety you suffer from a direct external source; only occasionally, but to a great intensity when you do. A fear of spiders or snakes, for instance. A man with acrophobia who finds himself atop the Sears Tower suffers intensely while he's there, but as soon as he reaches the ground floor, that fear leaves him entirely. This is the kind of fear that is a remnant of our primal instinct. The urge to escape from perceived immediate danger.
Existential fear, on the other hand, is the kind of fear that rarely reaches great intensity, but it's always there in the back of your mind, affecting everything you say, everything you do, and every decision you make. The fear of confrontation, the fear of disappointing your kids, the fear of not living up to your parents' expectations, the fear of being a bad wife, etc. This is the form of fear that is truly limiting and imprisoning. If the decisions that you make in life are in some way affected by the presence of that fear, then they are not truly your decisions. It's not truly your life.
When the self-help gurus talk about overcoming your fear, it is existential fear on which must be focused. It pisses me off no end when someone describes themselves using words like "overcome," "reinvent," and "conquer," but then proceed to jump out of an airplane or play with a fucking tarantula. This amounts to nothing more than masturbatory attempts at self-congratulations and it defeats the entire point.
Overcoming trivial fear is, well, trivial. This is because the fear you may or may not be conquering has no effect on the quality of your life. If some corporate executive could live his life over without his crushing fear of snakes, it's unlikely that he would've been an artist. A single man without his fear of heights would probably not have been married with kids. A grad student without his fear of dogs wouldn't have been a high-school drop-out.
However, a depressed middle manager without his fear of confrontation may well have been a wealthy entrepreneur. A lawyer without the fear of taking risks might have been a travelling writer. In any case, someone without the baggage of existential fear would be happier, even if only potentially. At the very least, they'll be making decisions - even bad ones - for the right reasons.
Letting go of fear in general is pointless, because some fears are good, and some fears have so little impact on our lives that eradicating them is wasted effort. The trick is first figuring out which fears are ruining your life.