Rittenhouse was born in Los Angeles, California. She attended University of Pennsylvania and later studied acting at the Atlantic Theater Company in New York City.She made her Off-Broadway debut opposite Blythe Danner and Sarah Jessica Parker in Commons of Pensacola written by Amanda Peet at Manhattan Theatre Club during 2013–14 season.
In 2014, she made her television debut, appearing in the pilot episode of Showtime drama series, The Affair. Later in that year, Rittenhouse was cast in the series regular role as Brittany Dobler in the Fox comedy-drama, Red Band Society.