"You should never change for anyone. And I say that because I've done it before; I've changed for a man... I was so, so in love with him that I'd have done anything. I look back now and think, 'What an idiot!' You only realise when you're out of it how someone can have a hold over you. He treated me horrendously and I just didn't help myself." British singer Ellie Goulding opens up about a failed relationship.