Kat Von D: Jesse James and I “Didn’t Break Up”

 Jason LaVeris/FilmMagic

Kat Von D and Jesse James are still going strong.

She recently fueled split rumors when she stepped out with ex Nikki Sixx at an Oct. 5 concert.

"I'm not dating Nikki," she told USA Today Tuesday afternoon while signing copies of her new book, The Tattoo Chronicles. "We didn't get back together. Jesse and I didn't break up."

The L.A. Ink star, 28, is proud of her relationship with the West Coast Choppers CEO, 41, who famously cheated on Sandra Bullock.

"I've known Jesse for a long time, since I was 22-years old," she says. "I think he's probably one of the most kind-hearted, intelligent human beings."

At the book signing, Von D was sporting a sparkly diamond rock.

She wouldn't say if it's an engagement ring.

"I don't know if I really feel comfortable talking about it," she said, adding that it was "from the 1900s … It's been an addition to all the rest of my jewelry and my Victorian collection. They don't make things like this anymore. There's no more craftsmanship in a lot of things."

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