The model and Doctor Who star have reportedly called time on their 18-month-long relationship.
A source told The Sun that it was work commitments and Matt's reluctance to settle down that led to the split:
"Whenever engagement and marriage was mentioned he was uncomfortable. He's still a young man and the thought of being tied down was a lot to digest.
"This has come as a surprise to everyone. It was thought they'd be together for a really long time because they were so into each other."
The pair reportedly got together in April 2010, before splitting in May. They then rekindled their romance in July of the same year.
Tools designed to ensure computer code in smart cars does not crash has been inspired by hungry penguins.
The rounded sleeping capsules send guests drifting into ocean before arriving on desert island by morning.
Sitting on the saddle activates the part of the brain responsible for learning, a study has claimed.
Scientists are appealing for more people to donate their brains for research after they die.
Life on Earth may have arrived from Mars on an asteroid, scientists have claimed.
Lunar mission scheduled at the end of 2017 could find out if beer can be brewed on the moon.
A bottle used to teach children how far litter can travel ended up on Scottish beach after 8,700-mile journey.
x Share us on Facebook