Why Did I Let You Go?

Hannah and Nathan were in a serious relationship for nearly a year, until Nathan got into the band. Now she's with James and let's just say, it's not the best relationship. She misses Nathan, but doesn't realise how much until she bumps into him on a break to London with James. He misses her. He wants her back, but what does he do about it? Will she do anything about her relationship with James, or just keep it the way it is?