How do i get my girlfriend her back???!!!!!!?

I am sorry to hear man. It just happened t me on the 8th of Dec. Same exact situation as you. Difference is, she didnt tell me why and wont talk to me. I am 21 and stayed in bed for 3 days crying on and off. The pain is something no human should ever experience. I cant compete with the other 2 answers but my advice to you would be to give her space and time. Be sure to not talk to her unless she speaks to you first. I know, its really hard. I find myself staring at my phone with the text ready to send and i force myself to not send it. Another thing, stay busy. The busier you are, the more your mind wont think about her. Now that doesnt mean you wont be thinking about her while doing things. It just helps not think to deeply about it. For me, i think about her every second of every day. No matter what it is i am doing, she is on my mind but staying busy helps me not think in depth about her to the point i get sick and feel like breaking down. You are on the right track to bettering your life. You cant let it get the best of you man. It will either make you or break you. Perhaps she just needs a little time, then next thing you know she is back in your life and things could never be better. I hope for the best man. Keep faith brother. One Love!