The couple, who married in 2005, are said to be heading for a £100million divorce battle.
A source told OK!:
"Often when Ben and Jen have a problem they agree to ride it out until they can get some time apart.
"Jennifer has close friends who think she and Ben are a terrible fit, despite how much he loves being a father to those kids."
Affleck, 42, and Garner, 43, have publicly gushed about their admiration for eachother.
Despite not commenting on the recent rumours, in Garner's most recent interview, the actress said:
"You just go on a ride together because you don't know who you're going to get with when you first have a baby and you don't know who (your partner) is going to be.
"You just have to hang in there while you figure it out."
The couple are parents to Violet, 9, Seraphina, 6, and 3-year-old Samuel.
Could it be goodbye Bennifer?