The former Pussycat Doll was snapped arriving at the Palladium theatre to prepare for her role in tonight's performance of Cats.
Nicole was dressed down in ripped skinny jeans, boots and a cosy jacket, and kept herself hidden beneath an oversized pair of sunglasses.
She will take to the stage tonight in Cats, where she's been receiving rave reviews in the role of Grizabella. Her final performance is on 7 February.
The starlet hasn't commented on claims that she and Formula One driver Lewis have ended their lengthy on-off relationship. According to The Sun, which reported the split this morning, the couple have called time on their romance over Lewis' alleged reluctance to marry and start a family.
A rep for Nicole told us they wouldn't comment on her personal life.
Nicole, 36, and Lewis, 30, began dating in 2007 and have split and made up in the past. They've both spoken about the difficulty of maintaining a long distance relationship when Nicole is jetting between the UK and the US and Lewis is at Formula One tracks around the world.
Lewis told ITV's This Morning last November that marriage and kids weren't on the cards for the couple just yet.
"She's amazing with kids. I think we're both pretty good with kids but we don't have time for that at the moment," he said. "There are so many things we want to do, but the great thing is that we support each other with it. All in good time! She's still massively young and I'm still young!
"With our careers people perhaps don't understand that she lives in LA, I live in Monaco and we're in and out all the time," he added. "Schedules are changing all the time. She's doing Cats now which means she's here [in the UK] for the next two months and I go away and do my training. So during the year we're always apart, but people can see there's a lot of depth there - we've been together for almost seven years."
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