Complex sentence: Gerwig worked with her boyfriend Noah Baumbach on his film "Greenberg" in 2010, and they co-wrote "Frances Ha", which was theatrically released in May 2013, after being screened on the festival circuit since September 2012.
Split into simpler sentences: Gerwig worked with her boyfriend Noah Baumbach on his film "Greenberg" in 2010. Gerwig and Baumbach co-wrote "Frances Ha", which was theatrically released in May 2013, after being screened on the festival circuit since September 2012.