Apparently Robert Pattinson had a hard time forgiving and forgetting. Us Weekly reported that the actor constantly brought up Kristen Stewart's past whenever the two got into an argument.

An insider told the magazine, "He really put her through the ringer."

"Ultimately, it was like, 'Either we move past this or we don't.' It wasn't good for either of them."

Towards the end of their relationship the couple got into arguments more frequently and Pattinson would always remind Stewart of what she did.

A second insider told the magazine, "Rob always brings up the cheating scandal to Kristen." The insider continued to say, "He hangs it over her head."

Although said to be devastated over the break up Stewart was all smiles when she was spotted Monday night hanging out in Los Feliz, Los Angeles.

Maybe it had something to do with her visit to Taylor's Swift's house, in which an insider told Us Weekly, that she spent all day at the singer's home before returning back to her house.

The actress was then spotted just one day after her now ex-boyfriend, Robert Pattinson, moved his stuff out of her Los Feliz home.

The Daily Mail reported that the 23-year old seemed, "relaxed and not showing a hint of hurting, Kristen leant up against a car as she chatted enthusiastically with her pals."

The site reported that the on-again, off-again couple has taken a break from their relationship of four years but are allowed to date other people and Stewart was finding it tough to deal with.

"They are basically allowed to date other people and Kristen is super sad over the whole thing.

"She has absolutely no desire to date anyone and the thought of Rob possibly seeing other people has made her sick to her stomach. She's depressed and rightly so."

"Her good friends have been hanging out with her at her house giving her support. This is a tough time for both of them. But Kristen seems to be taking the split the hardest."