Hello, I met a girl about a month ago in college. We would talk for about 15 minutes before class and I would walk her to her next class. I became very attracted to her, not just physically but in her mannerisms, and way of thinking. I finally asked her out last week and she agreed. I was over the moon. The day before the date, as I was walking her to her class, I wanted to make it clear that this wasnt a "just friends" situation. We sat down and as we were talking, I put my arm around her and she scooted in closer. We talked for a bit with some playful hand touching as she told me about a character she was drawing and his backstory. We headed to her class but I took her aside and I let her know that when I asked her out, I was asking her on a date. She said she wasnt interested in that so we called it off.
I have spent the weekend doing my best to purge the "what if" and the "she will change her mind" thoughts from my head. I have accepted (mostly) that she's not interested. In past, similar situations, I would just walk away and make no effort to stay in contact. If the girl reached out, I would respond but I wouldn't go out of my way to talk and whatnot.
I want to know how can you stay friends with a girl who you want to be with but doesnt see you that way.