Jennifer Garner’s Boyfriend John Miller Wants ‘Healthy Boundaries’ With ‘Codependent’ Ex Ben Affleck

Jennifer Garner and Ben Affleck might truly be Hollywood’s friendliest exes.

Despite divorcing nearly 15 years ago, a source tells Globe that the 53-year-old actor regularly shows up unannounced at her home, staying for days at a time.

Photos obtained by Page Six even show the former couple grabbing lunch together in LA on Friday, May 22 sans their three children.

However, it’s got Garner’s longtime boyfriend John Miller questioning where he stands in all this, the source reveals.

“John’s friends do not understand how he puts up with this,” admits the source. “They’re telling him [that] he needs to give Jen an ultimatum — that it’s either him or Ben — but there’s no way John will do that.”

The Cali Burger CEO “knows Jen wouldn’t react well,” the source notes, adding that while her relationship with Affleck is “undeniably codependent,” it’s also “the reality of the situation.”

All Miller wants are “some healthy boundaries,” Globe‘s source stresses.

“The problem is that Ben always uses the kids as the pretense for being around, so there isn’t much John can say, even if he suspects that Ben has ulterior motives,” explains the source.

“And there’s no point in having a man-to-man chat,” the source adds. “John says he’s tried that before and Ben has said all the right things and then nothing has changed. If anything, Ben and Jen seem to be getting closer.”

The amicable coparents are “even making plans to spend some of the summer holidays together,” reveals the source. “Jen has invited John to join them. She isn’t shutting him out, but the reality is he will be the odd man out. It will be like he’s joining their family vacation.”