Justin Theroux will marry Jennifer Aniston on his birthday.

The couple will reportedly tie the knot on August 10 - two years to the day the actor proposed on his 41st birthday - after undergoing ''months of therapy'' to talk through their problems.

A source told Britain's Grazia magazine: ''After talking honestly, their issues seemed to evaporate.

''Justin admitted he hated the idea of an over-the-top wedding. Jen's happily agreed to a low-key do with friends and family.

''Jen's thrilled and Justin couldn't be happier.''

Justin has reportedly agreed to relocate permanently from New York to Jennifer's Los Angeles home.

The source continued: ''Jen doesn't like Justin going to NY alone and lunching with his ex-fiancee Heidi Bivens.

''But once she offered him space to script-write, Justin agreed to move his office to Los Angeles.''

It was recently claimed the couple have been working on a script together.

A source said: ''They worked out a story idea and a list of characters, and when Justin went away on a job for a week, Jen was so inspired she just kept on writing - alone.''

But Justin was reportedly less than impressed with her efforts and it caused tension between the couple.

The source said: ''Jen got the message loud and clear, shrieking, 'Are you kidding me? You're the one who pushed me to do this. I told you I wasn't a writer. Justin wisely zipped it as Jen angrily ripped up her pages and stormed off.''