When it comes to "Here We Go Again," it isn't just the title of Demi Lovato's sophomore album. It just might be the thought going through the actress and pop star's head when she's asked for what is the umpteenth time about her ex, Joe Jonas.

Their relationship, sparked when they played opposite each other in the 2008 hit Disney Channel film "Camp Rock," was played out in public. As was their breakup in May. Lovato is the special guest on the Jonas Brothers' three-month world tour, which will kick off Saturday at the First Midwest Bank Amphitheatre in Tinley Park.

When asked how she is seemingly able to keep her personal life from spilling into her professional one, the 17-year-old singer had a simple answer. "You can't," she said sighing. "There's a line that gets crossed simply because people are watching your every move. There's nothing you can do but try and keep your private life as private as possible."

What does that mean? "I keep having a good time and living my life," she said. "I'm not walking on any eggshells." Lovato is trying to focus on the work ahead of her. There's the world tour, for one thing.

"It's going to be so much bigger than anything I've done before," she said. "We're adding dancers. I'm performing 'Camp Rock' songs and there are a lot of surprises." She added, "It's awesome. I'm so excited and the fans will enjoy it."

"Camp Rock 2: The Final Jam" premieres Sept. 3 on the Disney Channel, and Joe Jonas again plays her love interest. "The sequel is basically bigger and better than the first one," she said. "There's more dancing, more romance and more drama. I'm very, very proud of (it)."

Lovato said she can identify with her character, blue-collar teen Mitchie Torres. "I love how she is so driven and strong-willed," she said.

Lovato recently filmed the second season of another Disney Channel property, the comedy series "Sonny with a Chance."

If that weren't enough, Lovato has begun work on her second follow-up to her well-received debut CD, 2009's "Here We Go Again." For her third album, she wants to move in a new direction. "I think you'll see a bigger change from the second to the third album than you did from the first to the second," she said. "I'm experimenting with new sounds. I want this album to have more R&B this time around."

In particular, she said, "I know music has changed since their time, but I would love to work a little Billie Holiday, Aretha Franklin, Gladys Knight and Sam Cooke into it." It provides a place where kids can go to talk with other kids," she said.

Though painful, she credits bullying she experienced with becoming a better songwriter. "When I left school, I had no friends other than (actress and singer) Selena Gomez, and when I wasn't hanging out with her, I would write music. It became the only way I could get some of it out."