"Jen does not want to police who Ben dates because she is no longer his wife and doesn't feel it's her place," the source says. "It has been a rough few years and now they are just both relieved to be on the same page."
"They plan to work together and be the very best parents they can be,” the source says. "[Affleck's] focus is his sobriety and co-parenting with Jen. He knows his secrets hurt Jen in the past, but they have come a long way. They talk openly with one another about their lives and are friends.”
The source also notes that the actor isn't currently looking to get into a serious relationship -- but at the same time doesn't care about being seen with Sexton.
"Ben is having fun right now and keeping their relationship very light," the source says. "He knows it doesn't look good for him to be out and about with Shauna so soon after his break with Lindsay, but at this point he isn't concerned about how things look. He has been through so much in the last several years that he wants nothing more than to enjoy his freedom and focus on what is most important. Ben has come a long way with his sobriety. He still takes it one day at a time and probably always will.”
"Ben is single, and at this point feels he can date who he likes," the source continues.
As for the actor's relationship with Shookus, the source says he remains "grateful" for her support.
"Ben really cares for Lindsay, but he was in no way ready to settle down," the source says. "Lindsay helped him through one of the most difficult times in his life and for that he will always be grateful.”