I broke up with her yesterday :( and I feel awful :(

We are a young couple, I am 18 and she is 15. The relationship started almost a year ago, and it went fine almost all the time except for some little fights. During our relationship I found out that her parents mistreated her, they were putting unnecessary pressure on her to succeed in school and to not even have contacts with any guys. Sometimes they beat her up and I was the one who was there by her side to tell her that she has my support, although she demanded me not to go to the police or something. Another problem of her was that she didn't get to go out almost at all, they did not let her, and that is also the reason why I only met her once in our entire relationship ( it may seem like a joke or something, but even though we were chatting all the time, I really fell in love with her and I love her so much ). She went on the beach for the past 18 days, and now she comes back, crying, and tells me that her brother has threatened her, that if she doesn't break up with me he would tell her father and she absolutely did not want that. She told me we had to break up, but for ****'s sake, how can she give up so easily ? I am ready to fight for our relationship, but seeing she is not, I don't think it is worth it but I also love her so much, I just feel lonely without her, nothing matters right now that she is not talking to me anymore she asked me to stay without talking for one month, and then maybe we could talk, but I don't really know what to do.

I didn't really try to do anything about her family since I know these are internal family matters, but one thing I did was that I consolated her and I told her she has me and our love, something beautiful. She had a beautiful 18 days with her family on the beach, and now she suddenly tells me that she has understood that family is the most important thing in life, that she didn't know any way now to fight for our love and that she has chosen to learn hard instead of having a relationship. What wonders me in here is that I never even tried to make myself look as the most important instead of her family, I never even tried stop her from learning hard, I never put any kind of pressure on her for anything. It hurts cause till now I thought we were a beautiful couple, internet couple, but for me this was and still is more than internet love, cause I feel this girl, my heart beats for her, and I know it. She was planning to come to the town I live and finish her high school here, so we could also meet 3 or 4 times a week, but it's all gone now. I simply do not understand how could she possibly change so much for 18 days, her whole love for me. It's not like it was something simple over the internet. We exchanged lots of things with each other. Maybe some of you will laugh but sent intimate photos of each other to each other. We got deep into it, it was not something simple. I would need advice from someon experienced, who really knows what I am talking about.

We broke up yesterday :( I would really need some advice that is real and encouraging.