What should I do, I miss my ex I want her back but what can I do?

So im really sad right now I need some advice,

I broke up with my ex 2 years ago.. The reason was me, I tho shed be happier with someone else rather than me it was long distance relantionship What made her leave me was I wouldnt call her for like 2 weeks or a month, I know! Thats harsh But I tho it was better that way so she could be with someone near her.. But I still loved her after those years, then we met again last november wev been talking what happened and so on, she was so happy to see me as much as I, we wanted to try again Been good.. For 2 months.. She was really busy with college so we didnt had much time to talk, but I understood that But she suddenly told me im not good for you.. You should find someone else, im letting go..

I asked why? She told me because, she felt like guilty we didnt have much comunication because she was busy She didnt want me to wait everyday for her on the phone and in the end she wont be calling, just like what happened then.. And that she couldnt give the love im giving to her <- that really breake me into pieces

Finally she told me she wanted us together but she made a big gap so it was wrong of her

I dont know anymore if its just that, Havent talk to her for 3 weeks havent contact her aswell, I want her back for good but I cant do anything anymore, all I can do is wait and see whats gona happen in the future..

What can I do?