The 21 year-old had been dating the Inglourious Basterds actor for just eight months but work commitments are said to have got in the way of their relationship.
A source said to UK newspaper Sunday Mirror: 'Peaches is really sad that things didn't work out with Eli. They were very much in love and she'd never been so nuts about a guy.
'But both are hard workers and have huge work commitments coming up, so they were due to be spending too much time apart. It was almost better for them to part ways before things got even trickier with making time for each other.
'They remain great friends and her time spent with him will remain extremely precious - but it's all over now.'