The actress and Ricky Van Veen announced the news on Thursday, June 27 in a joint statement, insisting they plan to stay friends.
"With mutual love and respect, we have made the decision to separate as a couple," their release reads. "We are grateful for the friendship that we have and will continue to have."
Williams and Vimeo co-founder Van Veen wed at the Brush Creek Ranch in Saratoga, Wyoming in 2015. Tom Hanks officiated the ceremony and guests included the bride's "Girls" co-stars Jemima Kirke, Lena Dunham, and Zosia Mamet, and Katy Perry, John Mayer, and Seth Meyers.