Sean, antidepressants are not just for those who are depressed, it's also for those who have generalized anxiety disorder, which is what I guess that you have - not a doctor, but you show all the classical signs of it - and I can totally relate. Anxiety and depression are on the same spectrum, but at different end. Those with anxiety usually fear the future and those who are depressed, regret the past. There is also OCD, social anxiety, SAD, and a few others that can be helped with an AD.
You can most certainly find some relief with proper nutrition, exercise, cognitive behavior therapy, yoga, mediation, prayer and the like, but most likely you will only find temporary or minimal relief at best. I don't mean to sound like a drug pusher, because believe me I've been exactly where you are and fought the idea of taking medication. I tried everything under the sun, including acupuncture, massage, and journaling on top of what I've already listed, and I could manage and maybe have a few months that I felt okay, but the anxiety always came back.
If your anxiety isn't chronic and you only experience it every once in a while, then taking a valium is your answer. If, however, you have anxiety that keeps coming back and gets bad enough that you have trouble with every day activities, then perhaps you'll want to speak to a psychiatrist. Nothing says that you have to take what he/she prescribes, but I think you could get an education by speaking with one. Worse case, you walk out of there a little more knowledgable. Best case, you are given something that can help you live your life more normally.
Again, I will state, of course, this is your decision. I wouldn't try to talk you into something that wasn't right for you, I'm only trying to give you something of my own experience with the battle of whether or not to take an antidepressant for anxiety.