Kristen Stewart says her relationship with Robert Pattinson is stronger than ever - despite her cheating on him.

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The 'Twilight Saga' actress shocked the world when it was revealed she had had an affair with her 'Snow White and the Huntsman' director Rupert Sanders, but she insists she has learned a lot from her "mistake" now she and Robert are back together.

She told Mexican magazine 15 a 20: "You have to be OK with your own fears. If you're an honest person you'll make mistakes, but it'll be OK. The most interesting things happen after making mistakes."

However, it has been claimed Robert, 26, is finding it difficult to trust Kristen, 22, again and is being careful to take things slowly.

A source told a media website: "Kristen is working hard to try and force the relationship into what it was before.

"But the truth is, she's going to have to take it slowly with Robert because he's still having trouble trusting her again.

"For him to carry on like nothing happened is very hard. Kristen is eternally sorry for cheating on him and he has forgiven her - kind of."

While Kristen is adamant her relationship with married Rupert was never sexual, Robert is having a hard time believing her.

The source added: "The problem is he can't forget her infidelity. Kristen claims she never actually slept with Rupert, but Robert still has that nagging feeling of doubt that she did.

"It's too early for him to fully accept that they're an item again, but Kristen is pushing for them to go back to how they were."