Loosing my girl after proposing to her - she don't want relationship

(This is a bit long.. Sorry for any typos)
Hello, I am a middle class guy from South India. About me, I am in the 2nd year of my college. Age 19, I love spending time with frienda and stuff. I don't talk to girls much.. I only talk to them if I am in need of something. There's a girl in my class.. I didnt take much notice of her in 1st year. She was my batch mate during lab classes. It all started last year.. sometime around September.. I didnt know much about her .. neither does she know about me. I wanted to complete my assignment so I asked her if I could borrow her's. She was so friendly..
she gave her assignment.. The next day I wanted to return it to her.. When I returned it, she talked to me like we were friends for a long time.. nothing started for me yet. But I loved talking with her.. So I talked with her daily. we became good friends eventually. During weekends (holidays) I couldn't stop thinking about her.. I missed her daily. Finally, I realized that I was in love wih her. I felt bad, I know she would not approve it but I couldn't stop myself from falling for her. I got her number and texted her regularly. I would find reasons to call and talk to her in phone. We became good friends.. I felt like I was cheating her.. Around October, I asked her if she could come with me to select gift for my mom's birthday. She agreed but the next day she said she cant.. cause she was nervous since it was the first time and I was a boy.. I didn't force her.. said that's ok.. She noticed I was disappointed that day so the next day she said she will come.. as she promises, we went out and she selected a set of bangles.. That was the most beautiful day in my life.. I flet like I was dating.. I thought I had established a solid relationship with her.. i texted her every now and then.. And this year, January, I decided to propose her because I was becoming more and more insecure.. One of my friend told to wait a little long because I should know more about her but I didn't listen to him.. I proposed her at the end of January.. Her expression changed.. she didn't say anything.. I knew she would be disappointed so I stepped back.. I didn't disturb her for few days.. Meanwhile everyone in my class came to know about it.. I came to know that she was feeling bad.. I was sad.. after 2 weeks, I messaged her and asked sorry.. but she didn't reply.. She messaged me the next day and said she didn't expect this from me.. she asked me to forget it and be her friend forever. I said I can't even pretend like her friend
. she said she was feeling guity because of me and again asked me to be her friend.. I said no.. She then said that she's done with me and its my choice.. I was heartbroken for few days.. crying, long drives in bikes, talking to my own self, spitting at the mirror.. I know I should been patient.. Around Feburary, I came to know that her uncle was struck with dengue and is serious in hospital.. she circulated a message in my class requesting immediate need of blood of any group.. I immediately went to the hospital to donate blood. I went with 2 of my classmates (they are not friends with her).. she looked really sad
finally she talked to me.. she said the doctors are helpless with her uncle and they are gonna discharge him soon.. She thanked me as she felt better and said she wasn't expecting me to come such a long distance for her.. I said its ok and returned home.. she sent me a message thanking me.. Her uncle died the next day. She didn't come to college for few days.. After a few days , she seemd ok.. Meanwhile I couldn't go on a day without talking to her.. I decided to talk with her again but not anything about my feeligs.. so last night I called her and said I want her to talk to me like before.. She gave me an answer which shattered everything for me.. she said "It's impossible and let's be like this".. I asked her if she was serious and she sais yes.. I was broken and hung the phone with a bye.. After few minutes, she messaged me and asked what exactly is my problem..? I replied that I can't be without talking to her.. She questioned me how it's possible if I am not gonna see her as a friend..
I didn't knew what to say.. she msgd me to forget it and she's sorry.. She even asked me to do a favour and move on.. I said I can't and asked her to take care of her health and bid goodbye and that was it.. and here I am typing this with tears in my eyes.. I don't know what to do next.. Please, spare me a few words, gentlemen.

It was a really commendable expression of situation by you, what you did is nothing wrong and was not too soon either. You felt it, you did it but it didn't work, no problem in that. However, the problem here is that you are too young to get in any serious relationship and so that the girl also.

It takes time to get to a stage where you can't deny the attachment, you are at that stage but this girl is not . I am not saying to go again and force her into relationship but what mistake you did is that you got too serious, being serious at this age is not advisable, it gets kind of burden for other person as they don't want to hurt you by moving out of relationship.

So, may be this girl has some prior commitments, may be she is already in another relationship or there could be dozens of reason but we don't really have to care about them much. ..

Because, the thing you need to do now is very simple, get little funny with her, pretend that you want to start over as friend. Thats because only by being friend you remain in touch with her. Never be serious around her about relation (but everything else), be flirty with her and make her feel that her company gives you smile. But don't give burden of any relationship. Let the bond develop gradually and stop expecting anything from her on this relationship, just flow with it, give it some time.. you know what to do next.. It will also give you some time to know her better..

I hope you know what I am saying..