REUTERS/Eduardo Munoz
Anthony Weiner and wife Huma Abedin arrive at the Metropolitan Museum of Art Costume Institute Gala (Met Gala) in Manhattan May 2, 2016.
Abedin released a statement announcing the split after the New York Post reported that Weiner sent suggestive images and messages to a woman for more than a year between early 2015 and this year, including one image with his then 4-year-old son in the picture.
"After long and painful consideration and work on my marriage, I have made the decision to separate from my husband," Abedin said in the statement. "Anthony and I remain devoted to doing what is best for our son, who is the light of our life. During this difficult time, I ask for respect for our privacy."
Abedin has long been the right-hand woman for Clinton, the Democratic presidential nominee.
The latest scandal is one in a string of revelations about Weiner's sexting habits. His first sexting scandal drove him from office in 2011, while revelations that he continued sexting women helped destroy his bid for mayor of New York City in 2013.
Republican presidential candidate Donald Trump has had no qualms tying the former congressman's misdeeds to the Clinton campaign. Last month, the real-estate magnate called Weiner a "sleazeball and a pervert," and argued that Abedin shouldn't be an integral member of Clinton's campaign staff because of her husband.
Maxwell Tani contributed to this report.