I will comment the entire plot main conflicts, so there is a lot of spoiler, WARNED!

Ettore is just a failed father and husband who found in his miserable life an opportunity of having as he himself described " sex with a stranger " with someone.He is no position to teach her nothing about being a better mother, or having a better relationship. When Adriana was spotted by him in the mirror kissing Elena, he felt as the typical male peacocking-the-female clear attempt move with the piano very shocked and humiliated, as normal people feel when fooled into misinterpreting things, (in this case : the secret relationship between Elena and Adriana), and the perfect moment of convincement as she felt sorry for his stupid "sadly running away" escape, downstairs he makes his check presence by doing the utter disgusting thing possible: emotionally blackmails her, reinterpreting the obvious unattached sex they had had with " sex with a stranger "but there was some feelings too, there is always feelings right? i'm so humiliated and disappointed about my life now that I can't even realize how stupid I am.

And of course, it works, along with his maturity air soft speaking and finger to the lips gestures, he makes her dig her past and judge herself with a identification with his, and on social divorced woman roles as being resolved, up straight, planning and settled, she finds herself in the worst possible aesthetical analysis that could arise at this point, which is a dilemma between fake maturity(Ettore) and young reckless fun(Adriana).

The social bias points at the former and she chooses wrong, she chooses the lonely failed old clichê male, on a trip of regret, self shame and pity, portrayed as the moment of "finding herself", which is of course, as we well know in psychoanalysis, the best misleading way of dealing with a trauma (unexplained reality) passing a even more stupidly written narrative: " I was unconformed with the social norm of what a thirty year old supposed to be, and now I found myself* in this soft speaking old dude, whom I will get back to my ideal Ego and fit my requirements"

How not only the rarity of, the authenticity, and the naturality of the emergence of the feelings makes Adriana the more truthful, brightest and better suited for Elena's life and condition.

The great overwhelming defeat on the comparison:

With a fast thinking, young and proactive personality, the way Adriana would inevitably motivate her to make a visit to her child would have been fearless, enjoying and warmer, instead of insecure, unnecessarily cathartic and purgative as the old Dude made look like, in giving her the previous mentioned sad and shameful interpretation on her past life problems.

The rarity of a not so defined distribution on a Kinsey scale romantic affection, E. and A. make a much more unconscious, tacit and thus truthful connection, specially the way they both were much more honest about themselves in the development of their very accidental relationship, in opposition with the old man, which were comically intrusive and planned (like in the coffee meeting, where he went JUST to see her? seriously?)

And at the ending, where she can no longer be saved from the very much boring routine, monstrous relationship, when they hold themselves in the kitchen and talk about Adriana's intimate conversation, who was clearly one-side secretive, in a third person manner, as adults speak about a toddler, and her very inventive and quick punch lines who used to not be just funny for Elena are now perceived thru this nothing but suffocating aura of fake-maturity and resolution and are no longer attractive and fulfilling.

Two adults in the gaze of their mistakes, she who saw herself on him, by his confessions, are both a failure now, living on over-identification with the others failure she mistakes herself with a better person. Living in a cloister created by a stupid social norm, makes her unable to interpret her life on a free and new way, a affection originated not by actual love, but by an illusion, an emotional blackmail and regret generated affection.

Exchanging : "- if you say I won't go" with "sex with a stranger with a little bit of fake feelings" and emotional blackmail.

Because true love is always violent.

The end is left out with the prospect of a very sad news for A. since E. cannot fit their relationship on her clearly socially imposed life style, she can't be with her anymore, and they are both doomed.

The plot resolution is outraging and expectable, and falls so stupidly in traditional social establishments that it was painful to watch. And it seems to me the author was blind to it, what makes it not intentionally bad, but an unseen catastrophe for him, the one you end up thinking you did great.