How should I treat my stepmother?

Currently I’m a junior in high school, and my dad is planning on getting married. My soon to be stepmom was my childhood favorite adult woman, and she used to be friend with both my parents. My biomom performed her wedding ceremony to her ex-husband, which I was the ring bearer at, but that marriage didn’t last. Now that my parents are finally finishing the divorce (it’s been going on for 3 years now and I’m so thankful for it ending), my dad and my stepmom want to finally settle down.
Ever since I was little my stepmom has treated me as her own daughter, and loved me as such. I’m not sure how I’m supposed to trear her now that she’s going to actualy be my stepmom. I mean, she’s helped me through alot, but how do I treat her?