Jennifer Garner did NOT attend her ex-husband's wedding ... she had other plans -- shopping at Sam's Club!
The previous Mrs. Affleck was checking out the aisles at S.C. in S.C. -- Sam's Club in South Charleston -- over in West Virginia just before 4 PM. That's about the time all the festivities got underway in Savannah, Georgia, where Ben Affleck and Jennifer Lopez tied the knot for a second time.
An eyewitness tells TMZ, she was shopping with 2 guys, who looked like her dad and her boyfriend, businessman John Miller.
She was super friendly .,.. taking photos with fans and in a good mood.
To cure hazy memories, Garner and Affleck were married from 2005 to 2018 and have 3 kids together. Unclear how they're all reacting to the J Lo marriage, but at least on the surface, all seems fine.
There were reports Garner was invited to the wedding but passed ... we can't confirm that.
Meanwhile, back in Savannah, Ben and J Lo's wedding went off pretty spectacularly ... she wore an amazing dress with a 20-foot train. Can't find that at Sam's Club, for sure.