Hilton opened up about the ordeal during a joint interview with her mum Kathy on CNN talk show Piers Morgan Tonight, which aired on Tuesday night (31May11).
She says, "I just felt so betrayed. This was not some random guy, this was someone I was with for a few years. I thought I did (love him). I can't believe that he would do something like that to me.
"It's something that changed my life forever. This is not what I planned. I didn't want to be known as that.
"Now when people look at me, they think that I'm something that I'm not, just because of one incident one night with someone who I was in love with. People assume, 'Oh, she's a s**t', just because of one thing that happened to me."
Kathy was seen wiping away tears as the TV star continued, "I'll have to live with that for the rest of my life and explain it to my children. It's something that's changed my life forever. I'll never be able to erase that."
Morgan tried to continue his interview, but Hilton switched her attention to Kathy - who was silently weeping at her daughter's revelations - and gave a her a hug. Morgan then offered to cut to an ad break as a crew member handed Paris a tissue to pass to her mother.
Kathy explains, "It was a very difficult time. We had therapy, and I think that that really helped (deal with the scandal)."