@jackiesiegelusa / Instagram 1 / 4
@jackiesiegelusa / Instagram 1 / 4

For "Queen of Versailles" star Jackie Siegel, there will always be a part of her that's missing, and the pain from it will never go away.

Last summer, on June 6, her 18-year-old daughter was found dead in the family's mansion in Windermere, Fla., after fatally overdosing on prescription medication.

The case drew worldwide attention.

"There's not a day" that goes by where she doesn't feel like crying, she told Us Weekly Thursday in an exclusive interview.

"Sometimes I'll see a mother with her teenage daughter and I get emotional," she said. "I think by trying to save other people's lives, it makes us feel better that we're saving other parents from the grief we've gone through and that we'll always be going through."

Jackie, Victoria and the rest of the family came to public attention after the 2012 documentary "Queen of Versailles," which detailed the family's plan to build the largest single-family home in America during the recession.

Despite the family's wealth (they built a $100 million home, which they called "Versailles,") Jackie said addiction can strike anyone.

"Everyone from homeless people to billionaires' children are affected," Jackie told the mag. "It doesn't matter about race, financial status, if someone's addicted, no matter what, they're going to get it — they'll find a way, they'll steal, they'll prostitute themselves. And kids are so good at hiding the fact that they're doing drugs."

Victoria's family knew she had a problem before her death, especially after she went to rehab, where she fell in love with a man.

"They had an anniversary, a one-month anniversary, and on the anniversary, he cheated on her," Jackie alleges. "And one month, that doesn't sound like anything, but when you're a teenager and you're in love … She overdosed that night. She was trying to get out of the pain."

After her death, Jackie said the family didn't even return to their mansion for three months because they couldn't fathom the idea of Victoria not being there.

"We lost our inspiration. It didn't really matter anymore. Our passion wasn't in it," she said. "We put a lot of money into it, but it gave us perspective. I wish I could give up the house and get my daughter back, you know? It's a $100 million house. And I'd rather live in the house we live in now because it's full of all of our memories."