Like I said, you can choose to be happy, because you and your brain are so smart.
The cerebrum, the newer part of your brain (relatively speaking; it wasn't born yesterday) is more technologically advanced than the reptilian, where the emotion of fear is born.
If you begin to plow the field of fear as it becomes feelings (that is, as your cerebrum begins to process the original emotion), you can think about and route it out. You'll notice something fascinating: your brain may disguise what is really your fear as anything but. It might wear a three-piece suit of reasonableness, or it might turn into a "Waldo," so well hidden in the fibers of your other thoughts and feelings that you'll miss seeing it there for what it truly is.
Whose brain is it, anyway? It's not fear's brain, even though fear is tough. It's got to be; it has a tough job of keeping you safe. It just doesn't know that, in your technological world, not everything you're afraid of is a "fight or flight" situation. (Imagine yourself inviting a cave-man or -woman to visit your home full of DVDs and IPODs.)
Get in there and fight for yourself. Interrogate those feelings until you know you've shown them who's boss.
It is you, isn't it?