'RHONY': Luann de Lesseps Gets Emotional Discussing Her Father's Struggle With Drinking (Exclusive)

Luann de Lesseps wells up on 'The Real Housewives of New York City.'

In ET's first look at 'The Real Housewives of New York City,' Luann de Lesseps tears up talking about her father's drinking.

Luann de Lesseps is putting the "real" in The Real Housewives of New York City. In ET’s exclusive sneak peek at this week’s all-new episode, the longtime RHONY star is working on a memoir about her 2017 arrest and its aftermath, which included a nearly two-year-long probation sentence.

"That was weighing really heavily on me," the 55-year-old told ET in November. "It's finally behind me and I'm writing a book about the journey because, let me tell you, it wasn't an easy one and, and I think a lot of the reason why people are so into [my cabaret] show is, I talk about it, I joke about it, in my show. I self-deprecate about it because it was such a tragedy for me and so now, I try to make light of it, because it happened, it’s behind me and I think there are lessons to be learned from it. And, you know, I'm still learning those lessons and plugging them into my life."

In the first look, Luann meets up with the woman helping to write the book, and the conversation quickly turns to Luann’s late father, Roland Nadeau. For the first time, Luann reveals that her arrest reminded her of her young adulthood, when her father battled a drinking problem.

"He had 10 years of craziness as a drinker, and he got into trouble and got arrested and he, you know, had shackles on his ankles and as I'm sitting there [in the jail cell], I'm looking down at my ankles… I said, 'Oh my god. Now I can start to understand the pain and the struggle that he went through,' you know? And that's why he's…," Luann shares, tearing up. "I just ran across some pictures of him. I miss him so much."

Watch the emotional moment here:

"My father was everything to me," Luann adds in a confessional. "He was my rock. Growing up, my father struggled with alcohol. It was very difficult for me, and my family and my mother. Eventually, he stopped. AA saved his life, and I'll forever be proud of my father for that."

"Now, I can understand him so much more than I ever was able to as a young adult," she continues. "The struggles, they were real and I know how real they are, because I’ve had the same struggles. And he’s not here today, but I am."

Luann has openly discussed her own relationship with alcohol on RHONY, sharing stories from her time at Alcoholics Anonymous. She largely abstained from drinking for years after her arrest; she picked up a drink for the first time on camera a few episodes into season 12 of the show, a season that's largely been fueled by alcoholic antics.

"A lot of the women -- and I'm not naming names -- need to be more careful and more aware," she noted to ET last month. "I think it's time to check in with yourself. I'm not giving any advice to anybody on those terms, because that's going to fall flat coming from me."

"You know, I just take it day by day and I do the best that I can do for myself," she added. "But I feel like we could definitely reel in and on the drinking part. … I don't want it to define me. I've been doing the show for 12 years, and I never had a problem with alcohol except for the famous fall in the bush. But I giggled, I was happy at the time.”

The Real Housewives of New York City airs Thursdays at 9 p.m. ET/PT on Bravo.