David Letterman wasn't afraid to go there with Lindsay Lohan. On the Tuesday, April 8 episode of The Late Show, the comic grilled Lohan, 26, on her latest trouble with the law and with substance abuse.

"Aren't you supposed to be in rehab now?" Letterman asked the former teen star, promoting her cameo in Scary Movie 5."Do you not watch anything that goes on? May 2," replied a rattled Lohan, pretty in a short floral print dress, adding that her court-ordered, lockdown rehab stint will be for "three months."

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After Letterman inquired how many times the star has been to rehab ("several," she said), he wondered aloud: "How will this time be different? What are they rehabbing, first of all? What is on their list? What are they going to work on when you walk through the door?"

"We didn't discuss this in the pre-interview," Lohan said, then musing: "To be honest, I'm the happiest when I'm working and the healthiest, and I think this an opportunity for me to, you know, focus on what I love in life. And I don't think it's a bad thing. I think it's a blessing . . .and not a curse."

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"Yeah," Letterman agreed, "Perhaps a life saver, a career saver."

As the chat continued, Letterman made jibes about her shoplifting charges and many, many court appearances and admitted: "We'd never thought we see you again honestly because of the jokes and stuff. But yet you have enough spine, enough sense of yourself, enough poise to come out here and talk to me."

Struck by Letterman's compassion, Lohan then began to tear up, and he handed her a tissue and struggled to introduce a clip from Scary Movie 5. "I'm flustered right now, because you made me tear up because you're very sweet."

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Letterman also asked the star why she's "always in trouble." "I couldn't answer that," she said. "I'm a target. I've always been. I put myself in situations in the past where...I take full responsibility for it. And it wasn't funny. I was being immature. I was going through a phase. and I had a lot of family things going on and things in life. You grow up and you mature and, I've said that a million times, I know that. But what else am I supposed to say when it's a process of life?"

She added that she's "looking forward" to rehab. "I'm looking forward to some time for myself. The next time I come on the show, that will be in my past."

This article originally appeared on Usmagazine.com: Lindsay Lohan Gets Teary, Tells David Letterman I'm "Looking Forward" to Rehab