This song is about her relationship with Taylor Lautner. She says in the song that all through the summer they were close friends and enjoyed some good times together and when it came to fall she realised she was in love with him. However in the winter she starts to have doubts and when he comes and gives his love to her she simply rejects him. She's looking back on it now and regretting her decision. She is talking to him and trying to ask for his forgiveness and also wondering whether they could ever be together again. She says she goes "back to december all the time" meaning she constantly goes back to her memories of the night she rejected him and wishes she could change her own mind.