What a nerve Emma had, she was basically a serial cheater

Did anyone else think it was completely hypocritical for her to cast Adele out in such an uncompromising, unforgiving way when she cheated with her colleague? Because there are a number of indications (some quite overt) throughout the film that suggest Emma was in fact the real cheater out of the two, given that when she fist saw Adele, she was in a relationship with Sabine. In literally no time, she's with Adele and Sabine is out of the picture. Then there's all the signs near the end of her relationship with Adele that she was cheating with Lise. We see Adele's suspicion at the dinner party, as Emma very openly flirts with Lise. Then she refuses to have sex with Adele, blaming it on her period. That is a complete give away to me.

If Emma wasn't already sleeping with Lise around this point of the film, she was certainly having some kind of emotional relationship with her. So Adele, who was obviously in despair over the signs Emma was drifting away, and potentially cheating, goes out and seeks contact with her colleague. It wasn't even about "evening" the score board and getting back at Emma, she was simply alone, and hurting. Emma, who seemed to be a serial cheater herself, should have had more of an understanding for Adele. I do think that Emma was inherently a manipulative, lying person, and a cheater on top of that, who preyed on Adele's vulnerability and purity. Very sad situation indeed.