Ben Affleck has already been accused of cheating on Jennifer Garner with the nanny. Now reports say he had an affair with Lindsay Shookus, as well. And that has led to questions about when his marriage to Garner fell apart.

On Friday, reports emerged that Affleck was dating Shookus, a producer on Saturday Night Live. Initially, sources said the romance was fairly new. But it has since emerged that Affleck started seeing Shookus three years ago - before his split from Garner.

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"[They] full-on had an affair. They would fly back and forth, but he would mostly visit her in New York," a source told People. "They didn’t hide … They would use the Mandarin Oriental [hotel]. They were regulars."

And Affleck wasn't the only one cheating on his spouse. Shookus was also married at the time, to former SNL producer Kevin Miller. Shookus even reportedly left her husband for Affleck."They were having secret rendezvous every time he came in to New York City and other places, too," a second source said. "Both of them were cheating on their spouses so they were very careful about it. Jen and [Shookus’] husband both found out about it around the same time."

Lindsay Shookus - THR Lindsay Shookus spoke to Hollywood Reporter about her career in 2015.

Some sources claim that Affleck's affair with Shookus directly led to his divorce from Garner. "Lindsay was the main reason that Jen decided to leave Ben," another source told Us Weekly. "They had a multitude of problems, but this was the breaking point for Jen. This wasn’t just sex, this was infatuation and a full-blown relationship that Ben and Lindsay were having while they were both married."

There were other issues in the marriage besides Affleck's cheating. Insiders said at the time that Affleck's busy schedule also played a role in the split.

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But this isn't the first time Affleck has been accused of cheating on Garner. Shortly after the breakup, reports emerged that he had an affair with the family nanny, Christine Ouzounian.

Both alleged affairs occurred in the last few years of Jennifer Garner and Ben Affleck's relationship. The couple was married for 10 years, and things definitely seemed to go south in the second half of his marriage.

Christine Ouzounian Ben Affleck was previously accused of cheating on Jennifer Garner with nanny Christine Ouzounian.

It appears the couple really struggled after the birth of son Samuel in 2012. While he may not have directly caused any of Garner and Affleck's issues, the baby likely didn't help matters.

As more reports emerge about Affleck's various affairs in the last few years of his marriage, it seems likely that he was unhappy for a while. He may have just stayed with Garner for as long as he did for the sake of their kids.

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Garner has also agreed to put the children first. So she has set aside her feelings about Affleck's affair and tried to stay amicable with her ex. They even went to a Fourth of July parade with the kids last weekend.

Are you surprised that more cheating reports are emerging? Let us know your take in the comments section below!