LuAnn de Lesseps is willing to move past fiance Tom D'Agostino Jr.'s recent infidelity. The 51-year-old "The Real Housewives of New York City" star revealed in an interview with People that her engagement to D'Agostino is still on despite him kissing another woman. "I'm not going to let a stupid kiss ruin the rest of my life," she told the magazine. "He screwed up. What he did was wrong. But this wasn't premeditated. It wasn't an affair. It was a mistake." De Lesseps' co-star Bethenny Frankel had given the bride-to-be photos of D'Agostino kissing an ex-girlfriend at the Regency Hotel in New York. The incident took place after the couple fought the night before their engagement party. "He was upset with me," de Lesseps said. "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." Wednesday's episode of "The Real Housewives of New York City" will see de Lesseps confront D'Agostino over the kiss. A preview shows D'Agostino claiming not to remember the incident, although he now tells People he regrets his actions. "If I could take it back, I would," he said. "I deeply regret the mistakes I've made, and most of all hate the way it hurt Luann."