Wow, I really admire your dedication. However, you in a very early stage to making amends with her. Just concentrate on your sobriety for especially being 3 days in. Your mind may change or you may be moody from withdrawal. Your main focus needs to be having dinner without a drink.
If you contacted her out of the blue to tell her this she may be confused or think maybe you are seeking sympathy to get back with her. Ultimately the decision is yours. I wish you the best with your sobriety and dinner with her. Just remember Rome wasn't but in a day and your in a volatile stage.