updated 05/05/2014 AT 1:30 PM ET
•originally published 05/05/2014 AT 2:00 PM ET
The revelation brings Spelling to tears in the upcoming episode of True Tori – and seems to lead McDermott to an emotional breakthrough about his infidelity.
“We were at a Christmas event. I was taking pictures of the kids in fake snow,” Spelling, 40, tells her husband in a clip. “I had all four kids there by myself, managing them, and you called me, and we talked to you on FaceTime. And I was like, ‘Oh, Daddy’s busy, he’s working.’ And this is the memory I have of that Saturday.”
As she continues, McDermott , 47, winces in pain, describing the feeling as “like an ice pick through my head.”
“I feel shame. I’ve never felt shame before,” he says through sobs. “You were at a Christmas event, and I was f––king around. That’s disgusting. That’s disgusting.”
True Tori airs Tuesday at 10 p.m. ET on Lifetime.