Following Kristen Stewart and Robert Pattinson's break up the actress confronted his new rumored fling Riley Keough in a heated phone conversation. Then over the weekend "The Runaways" co-stars came face-to-face.

Stewart, 23, and Keough, 24, had their encounter while out enjoying Joan Jett's concert at West Hollywood's House of Blues. The two girls have clearly become friends with Jett after starring in the biopic that depicted rock star's life.

The "Twilight" star played Jett while Keough portrayed Cherie Currie's sister Marie.  On the night of the concert while sitting upstairs in a VIP section called the Foundation Room with three friends, Hollywood Life reported that actress had an awkward moment when she saw Riley Keough.

"It was weird when they saw each other, because Kristen didn't look very happy when she walked over to give her a hug," an eyewitness told the gossip site.

The source added, "They spoke for like two minutes and then Riley and her girlfriend walked away

"Kristen watched the show from upstairs and I am pretty sure Riley kept her distance and was watching from downstairs." For the rest of the show the actresses were careful to avoid one another.

However, Stewart's bad weekend didn't end there, the actress was mocked by fellow actress Lindsay Lohan as she shot a guest spot on "Chelsea Lately."  

When speaking about Stewart's explicit rant against a paparazzo, Lohan said, "I'm just excited that Kristen Stewart, you know, finally showed some emotion."

"The Canyons" actress tried to justify her offensive comment, saying, "No, I really do love her. She's awesome. I'm a Kristen Stewart fan."

But went on to say, "I will say this, of course she hates photographers - they got a picture of her kissing a married man in a Mini Cooper."

While Stewart has clearly had an eventful weekend it looks like her ex-boyfriend is struggling to get on with his life post-split.

According to Hollywod Life, an insider said, "Rob's trying to reclaim his life after splitting up with Kristen. He loves that Twilight was huge and he's set for life because of it, but he's resentful of the media firestorm that descended on his personal life.

"He's the kind of guy who wants to quietly chill with his friends and date a down-to-earth girl. Kristen was that for a bit, but their relationship made him unable to leave the house, and he hated that."

The insider added that "At this point, Rob's just going to focus on making great cinema and hanging out with his friends and hooking up with girls. He's definitely not dating Riley [Keough] or anybody else seriously."

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