When I started college, at 16, I fell in love with a girl (first love). I was inexperienced with relationships so I allowed myself to put her on a pedestal etc. so I ended up falling in love with her. Then she started giving off every sign in the book towards me, she definitely liked me to some degree as well. She treated me like a king in class haha. I loved it. But the whole situation came on very fast, and I was struggling to cope with the feelings and the pressure of doing something to get into a relationship with her. A month of this passed, and she ended up getting back in a relationship with her ex. I was heartbroken and unsure what to do. My emotions were all over the place. But her ex didn't go to the same college so they weren't really together much, so I carried on with the situation thinking I still had a good chance to win her over, but I didn't want to do it whilst she was in a relationship so I planned to stop all the signs I was giving off. But she made it difficult. She kept giving me signs that were difficult to ignore (eye contact to be specific, and it's kind of difficult to not, even accidentally, look at your crush when you get the chance so I ended up giving off eye contact occasionally). Anyway, she kept giving off these signs even though she was in the relationship. I thought she was leading me on and I grew a bit of anger to her for trying to continue it on, so I tried to make a statement to her and always controlled myself around her to prevent giving off signs. I did it, and she seemed to stop. Then, she got single again (without me knowing) and started the signs again. This happened again for a month or so again and then she got with one of her friends (a guy ofc). I didn't know this though. And she kept giving signs for at least a month. I didn't want to make any moves though because I wanted to know if she was going to be loyal this time, so I wanted her to wait. So after about 1 and a half of a month, I started messaging her when the signs were at the highest they had ever been. She barely showed any attention. She gave one word replies, and never took ages to reply. I thought I did something wrong and I was really confused. She kept the signs on for a few days but I could tell she was trying to pull away, and the signs she were giving off seemed without intent. After a few days, she pretty much stopped the signs, but I kept going. I kept messaging her. Then I started flirting with her. I called her 'cute' in a photo, and she just said 'Aww. Thanks' (Baring in mind she had a boyfriend still... but I still didn't know). I stopped after that empty reply. A few weeks later, I found she had a boyfriend. I was heartbroken again.
Anyway, a year has passed now and she is still in the relationship with that guy. They seem happy. And I obviously don't have feelings anyway and view it as a memory and a situation which I have a bit of regret over not doing much about. I'm moving to university this year, hopefully, and I was thinking about whether to talk to her about the situation on Instagram and get closure, and her perspective on the situation. I don't really mind, but I thought it might be nice to get that closure and maybe get some self-confidence in talking about how she might have felt about me (again, I don't need it but my thinking is that it can't hurt). I know she is a kind person so I don't think she will reject talking about it or anything unless if she genuinely has issues talking about it, like the boyfriend or something like that.
What do you think? Should I try to talk to her about the situation (even whilst she still has a boyfriend) or not?