The 31-year-old model and 43-year-old comedian embarked on a trial separation in February, but Lara has now left their luxury home with their son Alfred, two, and dog Bert, in tow, apparently putting a final end to her and the 43-year-old comedian's five-year marriage.
A source said: ''The fact she's moved could suggest the marriage is definitely over.''
Lara has now moved to an upmarket London area just three miles away from the marital home but her new house is ''a lot smaller'' than the mansion she lived in previously.
Speaking to The Sunday People newspaper, the source added: ''Lara's new place is a lot smaller than the huge mansion she shared with David but she seems to be enjoying life and is often seen having breakfast in a local cafe.
''The home is not as grand as people might expect but it has a lovely, traditional feel about it and it's in a lovely part of town.''
It is thought Lara and David - who wed in 2010 - have not yet formalised their split or reached any financial agreement. However, the 'Britain's Got Talent' judge was seen without his wedding ring for the first time last month and insiders said he has accepted his marriage is over.
A source previously said: ''David was holding out hope that he and Lara would stay together. But after going to America this month he realised he needs to try and move on. This is the first step in that direction.''
What's new in the music world this week?
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