Gwyneth Paltrow is acting as Cameron Diaz's life coach.
The Iron Man actress is helping her friend - who turned 40 last August - make some major decisions and has advised her to give up men because Cameron's romantic liaisons "distract" her.
"Gwyneth's sorted out everything from finances to hooking her up with her trainer. She has also forced her to swear off sex for a year, saying men distract her focus," a source told The Sun newspaper.
The two friends have been spotted out together regularly in the past year - after having became close after the death of Gwyneth's television producer father Bruce Paltrow in October 2002 - and Gwyneth, 40, previously hoped to find the perfect man for her bubbly pal.
"Gwyneth is a nurturer. Cameron is bummed about being single, so Gwyneth sees her as a project. She's trying to set her up with guys," a source explained.
The fun friends also gatecrashed a wedding show last year at the Sir Christopher Wren Hotel in Windsor, Southern England, while the blonde beauty was visiting the UK to promote her film The Counsellor.
Cameron has previously dated several famous men, including Justin Timberlake, baseball player Alex Rodriguez and Jared Leto.
Gwyneth is married to Coldplay frontman Chris Martin and the couple have two children, daughter Apple, eight, and six-year-old son Moses.