Do I still have a chance

About a month ago this girl and I started snap chatting and talking. We are both in college and have a class together so we know each pretty well. We also are sophomores now and we have been in the same friend group since the beginning of freshman year. We talked and hung out pretty often, we were pretty much in a relationship just nothing really "official". I didn't know this but when we were together she told me that she had liked me since fall semester of our freshman year at school. That's a year and a half which is a really long time. And I know she wanted to have a serious relationship because she's not one to do the hookup/quick relationship type and I'm the same way. She was really busy with school, work, etc. I was also somewhat busy and i got kind of frustrated with how busy we both were. I never actually got to take her out on an actual date or anything. It was just casual hanging out for usually 20 or 30 minutes and on a good day a couple hours. We never really got to spend that much time together. I ended up feeling like things weren't gonna work out so I talked with her and I told her that I didn't feel like things were working out and that we should cut off what was happening. The next couple of days/week were really hard on me because I couldn't figure out if I made the right choice. We agreed to stay friends because we were in the same friend group and were good friends before we tried a relationship so we took a couple days off from talking. A couple days later she snap chatted me and from then on we just casually talked, snap chatted, and texted every now and then. I started to fall for her again and see how amazing of a girl she was. I ended things on a Thursday and 8 days later I asked her to go to lunch with me and told her that I really really still liked her and that I 100% screwed up. I asked her to reconsider and she said she'd like a few days to think about it. She took 3 days and she said that she thought we should remain friends and not go further with things. She said that she felt like she didn't have those feelings for me anymore and that she didn't want to start things up again. I told her how much I like her and that she is someone that I can't lose, I told her how I felt and how much she meant to me. This completely broke my heart, this girl is one of a kind and I cannot lose her. I feel like she is somewhat confused and stressed out with school right now. Her roommate said that she felt like she is really busy and stressed with things and just trying to figure things out. This makes me think that she is just confused and is letting those things keep her from a relationship. I talked with her roommate and she said that I shouldn't fully give up on the idea of a relationship with her. I don't want to give up on the idea but I really don't want to wait any longer because it's been another week and I'm a mess right now.
I guess my questions are:
1. She liked me for a really long time before we started talking, and can that strong of feelings for someone go away in a matter of days? I just feel like she has to still have feelings for me.
2. Do you think she made this choice because she is stressed out and really busy and somewhat confused?
3. Is it fair to text her or ask her if she has been struggling with her choice and still thinking about me? because I've been thinking all day every day about her.
4. Do you think she still likes me and I just need to give her a little space and she'll come back to me? Is there still a chance?
5. What should I do?

Thanks for the help.