So me and this girl dated for 3 years we met at school when we were both only 12 we were sooo in love with each other we broke up and got back together a lot of times before and it was all for silly reasons like talking to some other girl late on Facebook and breaking a promise and now we broke up like a year ago I tried the no contact way but she didn't come back I know that she wasn't dating someone else through out the year and I want her back but I don't want to beg! Because I always ended up begging for her back and humiliating myself. PLEASE PEOPLE SOME ADVICE.

Leave her alone.
At 15, maybe she has grown out of that phase of her life. She has moved on, you need to do the same