It is certainly natural to feel a little scared when the boat heels in heavier wind - hopefully most of us were built with a good healthy desire to stay above water and on top of the boat.....
All the suggestions above sound great, even (although I hate to admit it) the suggestion to look at catamarans if you can't overcome your discomfort with heeling. You will probably "get over it" for the most part, however, with a little experience and more time at the helm. My youngest son used to put on his PDF/harness and lash himself to one of the rails/cockpit lines any time the wind was over 5 knots and the boat healed enough to be able to tell. Now he just climbs for the high-side rail and begs to "go faster."
Good luck and keep at it. We're all pulling for you.
Saginaw Bay, Michigan
"The pessimist complains about the wind; the optimist expects it to change; the realist adjusts the sails." - William Arthur Ward