MEMPHIS, Tenn. (CBS News) -- Rep. Steve Cohen (Dem., Tenn.) admitted Thursday that the woman he believed for three-and-a-half years was his out-of-wedlock daughter is not related to him.
In an exclusive interview with CBS News correspondent Jan Crawford, Cohen said, "I was totally stunned. I almost -- to me it was almost a lark, because there was no way."
In February, Cohen said he was the biological father of Victoria Brink, a Texas-based aspiring swimsuit model nearly 40 years his junior, who he believed was conceived during an affair he had with Houston lawyer Cynthia Sinatra.
"I Googled her mother, and found out that she had a child, and figured out through that, the math looked pretty accurate," he told reporters at the time.
Cohen tweeted at 24-year-old Brink during the 2013 State of Union address, saying, ""Nice to know you were watching the State of the Union. Happy Valentines Day Beautiful Girl." He added, "I-L-U," Twitter shorthand for "I love you." The tweet immediately raised questions about the possibility of an illicit affair.
Cohen swiftly deleted the tweet and explained, "The young lady was my daughter. And it was most appropriate that I responded to her and told her I loved her, and which I do."
Several months later, CNN provided Brink with a paternity test that revealed there is a zero percent chance that Cohen is her biological father and confirmed that Houston oilman John Brink is.
"The results show that Steve Cohen is not my father," Brink said Thursday.
Cohen issued a statement saying he was "dismayed" and told CBS News, "I loved her, I did everything in the world for her, tried to show her what I can of my world."
He also explained why he didn't subject himself to a paternity test several years ago when he first suspected he might be Brink's father.
"I didn't have children, I was thrilled to have a daughter, and I didn't want in any way at all for her to think that I was questioning the relationship or trying to avoid the relationship."
Cohen says he doesn't know yet whether he will continue to have a relationship with Brink, but tells Crawford he texted with her Thursday.
"I care about Victoria greatly, I have her pictures in my office. She's a very sweet young lady. For three-and-a-half years, I had a daughter, and it was nice to care about somebody and share," he added.
Cohen said he paid for the paternity test results made public Thursday on CNN's "New Day" at Victoria's request.
Cohen raised eyebrows with his social media conduct as news of the paternity test broke on Thursday. When a female reporter asked about the DNA results, he responded, "You're very attractive, but I'm not talking about it."
© 2013 CBS Interactive Inc. All Rights Reserved.