Fans of Real Housewives of New York were shocked to learn that LuAnn de Lesseps and Tom D'Agostino announced their plans to divorce earlier this month — and the Bravolebrity just opened up about what finally caused her to pull the plug on her marriage. The former couple wed on New Year's Eve, though their relationship was plagued with cheating rumors from the start, which we watched play out on the small screen.

LuAnn appeared on Watch What Happens Live on Monday, where she opened up to host Andy Cohen. "It was like the weekend before the reunion basically, and Tom went out and he called up an old girlfriend and they met up with a group of people and I didn’t know about it,” she says in the clip. "I found out about it the next day in the press so that for me was, like, the final straw. I was like, 'I can’t do this anymore,'" she explained.

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Fans may also remember that her co-star Bethenny Frankel caught Tom kissing an ex-girlfriend at NYC's Regency Hotel the night before their engagement party. At the time, she defended her man, telling People, “I’m not going to let a stupid kiss ruin the rest of my life. He screwed up. What he did was wrong. But this wasn’t premeditated. It wasn’t an affair. It was a mistake. He was upset with me. It was a stupid retaliation of some sort. He did the wrong thing, and he totally recognizes that. I know in my heart of hearts that he loves me.”

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Then, during the reunion, the mother-of-two made clear that she would NOT stand for Tom cheating again. She said at the time, “I would definitely leave. I would. After I kill him. I’d kill him first and then I’d leave. You can push me so far but once you push me over the line…”

We hope this housewife finds her soulmate soon. She deserves it!