One last question before the boards are closed down

Is there any reason why the director never showed Adele sleeping with her male colleague? Did he want us to question whether or not it actually happened? There are so many sex scenes in this movie (some might foolishly argue too many) her sleeping with the colleague would actually be an important one to have shown in the movie. I watched it again for the 5th time yesterday and I'm now questioning whether she actually slept with him, remember it was only shown, them kissing twice. Also, during the big fight with Emma Adele was adamant that she only drunkenly kissed the colleague (before finally "admitting" to it) I don't know I just feel like if it were supposed to be implicit she did it, then the director really failed us by only showing them kissing.