I was on Lorazepam (Ativan) 10 years ago in the initial stages of getting on Paxil. Valium I've never tried.
Xanax can cause dependency just like any other drug (ADs, crystal meth, nasal sprays, Tylenol PM), and cause addiction if it's abused. If it's not abused and taken as directed, then you'll be fine. If it's complete phobia/fear prevention you're looking for, look into longer acting benzos like Xanax XR or Klonopin on a daily basis. If it's situational, then I imagine any short acting one would give you equal benefit. If you want to avoid withdrawal effects, structure a tapering off schedule w/ your doctor. Never take benzos long term (daily) and just quit suddenly. The withdrawal can be horrific, just like many anti-depressants, crystal meth, nasal sprays, and Tylenol PM! (Well, not so much the last 2 but I think you get my point.)
Some people get alot of benefit from cognitive behavioral therapy while on a benzo and then when they are ready, wean off the drug. You may want to look into it (desensitization to vomiting is a common practice w/ CBT therapists). I personally cannot grasp or absorb anything my therapist says unless I am in my right mind to start with, which is where Xanax puts me. I've been on it daily for one year now.