She always avoided the topic of love, and I was conflicted…Help!

It's like this. She was my high school classmate. We were good friends, but I liked her. I once sent her a message to confess my feelings when I was in my second year of high school. This was the first time I really liked a girl, and it was also the first time I confessed to a girl. However, she rejected me. She replied,"I'd better not. Otherwise, we can't even be good friends." I didn't continue. From then on, we were good friends, but I always loved her. I never confessed to anyone again. Now, my first love is still in my hands. It's been nearly three years. I'm now a sophomore, and we've always been friends. She repeated a year, and now she's a freshman. After entering university, she has more time, so every night, we would call and chat for a long time. We talked about everything. I was very happy, and she kept smiling…However, whenever I mentioned her or my views on love and whether she had a partner, she would always avoid it…I want to confess to her again, but I really don't know what I should do now... Oh, I forgot to tell you. She's a very quiet and introverted girl. Just like me, she's never been in love. In high school, she always worked hard to study. She was very cheerful with her friends, but she was very quiet with strangers. I really couldn't figure it out. Yesterday, on her birthday, I gave her a box of heart-shaped chocolates. I was a little regretful at first, afraid that she would overthink, but she was very happy. To be honest, I really didn't have any feelings for other girls…Sigh...