Jon and Kate Gosselin’s 10th Anniversary Is Today

Jon and Kate Gosselin's 10th wedding anniversary is today.

But it's tough to tell whether the parents of 8 — who reunited this past week at their Pennsylvania home after spending two weeks apart as Kate vacationed with the kids in North Carolina — will be celebrating.

See the Gosselin family through the years

In May, Us Weekly was the first to report on the couple's crumbling marriage, detailing how Jon had an affair with 23-year-old school teacher Deana Hummel. (Despite on-the-record interviews and a video, Jon has denied an affair.)

See more controversial photos of Jon and 23-year-old girlfriend Deanna Hummel

The latest issue of Us Weekly (on newsstands now) now reveals that Jon cheated on Kate's 34th birthday in Utah — and has exclusive pictures of him and his mistress. Fans of the TLC show were saddened to see how much Jon and Kate had changed after watching the season 5 premiere – which drew a record 9.8 million viewers.

See what Kate Gosselin looked like in high school

"I am thinking this possibly could be our last family picture together," Kate said of a photo taken at the sextuplets' recent fifth birthday party. "I don't know…parents of multiples have, like, triple the divorce rate, and I was thinking we were gonna beat that. I don't know if I can say that anymore. Very swiftly, we turned into two different people, and that's just hard. I've tried for six months to figure out what the problem is, or remedy the problem. It's so complicated."

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