Your post reminded me of a similar one I made two years ago when I had my THR, Franny. I was very anxious, too, but support on here made me feel much better.
I can honestly say the THR has changed my life and I'm sure you will find the same. The worst part is the first week or so when you have to take a lot of medication, wear an elastic stocking 24/7, get used to having 90 degrees between lap and chest when you sit, and to sleeping on your back. All these things pass and the best thing is, you will find you can get around quite well quite soon.
You will need crutches for a short time (they are really not difficult to get used to and the hospital physios will teach you how), followed by a stick and then suddenly you will find you are quite confident to walk with no support (you will be told when it is safe to do this).
Make sure you do all the exercises (the physios will give you an exercise sheet), eat well and go for a daily 'walk' in the fresh air as soon as you are able (I crutched down our road a little way on the first day out of hospital and went a little further each day).
I am very lucky in having a supportive DH who was happy to change dressings (the wound is nothing like as nasty as you probably imagine) and TBH we had quite a few laughs along the way.
All the best for your op. You will be glad you had it.