Is it normal to be this close to a teacher after so long?

So I had this one teacher a few years back, and she was by far my favorite teacher and still is. I always liked her, but as I grew up, I learned to appreciate her even more and slowly began to realize how much she changed my life. She was my teacher for one school year, but she also ran some clubs at the school. As soon as I was out of her class, I joined her club. We became pretty close because she was a lot more relaxed and friendly with the kids who joined her club than she is with her actual students. Then I switched schools. I still live in the area, so at least once a school year I would try to visit her to catch up. I came by again this school year and found out that she has had a VERY bad year. Like she straight up lost everything important to her in the span of like 15 months, and I was so hurt knowing how hard her life was because she doesn't deserve it at all. So I wrote her a really long, heartfelt letter explaining how important she was to me and how I wouldn't be who I am today without her, and she was very appreciative of letter. We also text each other very occasionally. I'm about to go off to college, and she said she wants to help me shop for my dorm and go out to lunch or something before I leave. Is this normal?