I, like you, was worried about using the rotary cutter, and I avoided it at first....having my sister cut my fabric for me. I got braver, bit by bit, and realized it just took practice. What also helped me is the June Taylor Shape Cutter, which cuts strips that are straight...or at least mine were...even when I was a beginner. I couldn't cut out fabric for a quilt without it. It is so handy for more than strips. For example, cutting four inch squares is easy....cut a four inch strip..or three of them at once, and then turn the ruler and cut four inches again.
At any rate, if I can get comfortable with a rotary cutter, you can. (and I have no eyesight in one eye....) I have been quilting for a little over 3 years.
Good luck. With a little experience, you will become confident. You can do this.
Dina