Lamar Odom Opens Up About Ex Khloé Kardashian on 'Celebrity Big Brother' : 'I Miss Her So Much'

"I wish I could take that time back," the former NBA player says in a sneak peek at the Celebrity Big Brother premiere

Lamar Odom is opening up about his lingering feelings for his ex Khloé Kardashian.

In a sneak peek at Wednesday's season 3 premiere of Celebrity Big Brother, he tells fellow houseguest Todrick Hall, "I dreamt [about] my ex-wife last night."

When Hall, 36, inquires about who he's referring to, Odom, 42, says, "You don't know her?"

Hall then asks how many ex-wives he has, and the former NBA alum replies, "Just the one and only."

"Do you guys still talk?" says Hall, recognizing that Odom was talking about Kardashian. "No, I miss her so much," Odom says. "I wish I could take that time back."

Odom tells Hall that he and Kardashian were married for four years, before repeating, "I miss her so much."

Allen Berezovsky/Getty Images; Alexander Tamargo/Getty Images

Kardashian, 37, and Odom were married from 2009 to 2016. The former athlete last spoke out about the Good American mogul amid the drama surrounding another one of her exes, Tristan Thompson.

Last month, Thompson, 30, posted a message on his Instagram Story confirming that he fathered a child with Maralee Nichols, the woman who has sued him for child support and other pregnancy-related fees. (Thompson previously disputed the paternity of the child, who was born on Dec. 1).

In the message, the Sacramento Kings player also apologized to Kardashian, 37, whom he was publicly dating during the time he admitted to sleeping with Nichols.

"Khloé, you don't deserve this. You don't deserve the heartache and humiliation I have caused you," Thompson wrote. "You don't deserve the way I have treated you over the years. My actions certainly have not lined up with the way I view you. I have the utmost respect and love for you. Regardless of what you may think. Again, I am so incredibly sorry."

Odom, meanwhile, later commented on a Facebook page that had re-shared Thompson's apology, according to the Instagram account Comments By Celebs.

"I truly wish nothing but the best for her and I'm hoping we can reconnect and talk one day as friends," he wrote of Kardashian. "She is a good person and deserves the world."

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Kardashian and Thompson, who share 3½-year-old daughter True, had an on-and-off relationship for years before splitting most recently in June. Thompson also has a son, Prince, 5, with ex-girlfriend Jordan Craig.

Season 3 of Celebrity Big Brother premieres on Wednesday (8 p.m. ET/9 p.m. PST) on CBS.