Jennifer Aniston punched her ticket to cougar-ville in February 2008 when she started dating John Mayer, nine years her junior. Things got complicated when the unlikely couple hit a rough patch six months into their romance. “John took the decision to end things as he felt he just wasn’t ready for the level of commitment Jennifer deserved,” a source told The Mirror. The two resumed their relationship shortly after the initial split, but ended things for good in March 2009. A couple years later, Aniston, landed in the arms of actor Justin Theroux, only three years younger her. The two hit it off immediately and now engagement rumors are swirling, but nothing has been confirmed.