Kristen finds herself standing near Liberty while watching a band with Robert Pattinson

Kristen Stewart endured a very awkward moment at Coachella last weekend when she bumped into Rupert Sanders‘ estranged wife Liberty Ross.

The Twilight actress, 23, and boyfriend Robert Pattinson ended up standing next to Liberty, 34, and her new man Jimmy Iovine while hip-hop group Jurassic 5 performed.

Director Rupert, 42, and Kristen were caught cheating on their partners with each other last July and mum-of-two Liberty filed for divorce in January.

Robert, 26, has managed to forgive his girlfriend for being unfaithful and the pair have been snapped together numerous times over the past few weeks.

He didn’t seem too fazed by seeing Liberty and was later said to have been ‘grinning like a Cheshire cat’ after enjoying a beer with his idol Damon Albarn backstage.

But Kristen wasn’t in such a good mood.

Kristen has tried so hard to put everything from last year behind her – and she still feels incredibly guilty,’ a source tells The Sun.

‘She and Rob had turned a massive corner in recent months and they were both there to enjoy themselves.

‘The last thing she wanted to do was make Liberty feel uncomfortable, either. She looked pretty upset in the backstage bar later on that evening.’

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Anna Duff