For long-term reliability it's hard to beat the Toyotas.
Among domestics you might consider the 2011-2012 Ford Fusion (not the one in the photo). Honda Accords are also nearly always safe bets. And with a Hyundai Sonata or Kia Optima you'd have a 5/60 factory warranty. (You'll see some yellow faces in our stats for the Koreans; these are largely due to one very common failure for which they've now been recalled.) We don't have as much data on the Mazda6, probably because they didn't sell many in 2011 or 2012. The 2009 and 2010 are still looking good, though.
It's hard to narrow down the list without knowing more about what she likes and dislikes in various cars. Maybe take her on a few test drives and report back : )