you know wht this manga gives me a fear towards the reality a man can't be with the same w...

Don't worry, men aren't supposed to be like this at all. If a man really loves you, he will eat the same meal everyday forever, because he will always love it every time. Cheating isn't natural for someone in love.

yah i guess so...but it might be really hard to trust ...i guess

It is because the mother allows that behavior, that her husband does, because the mother doesn´t want him to leave, and he knows it and takes advantage of it.
If one day your boyfriend or husband is with another woman (In "that" way), and you discover it, don´t let it go with a "It's in the nature of men", "If I endure I protect the home", and so on (They're just excuses to give you a martyr-type satisfaction).
They only do it because they think that it is normal in their nature (Like a game), that it can´t be avoided, they know that the woman will depend on them, and she won´t want to abandon them even if he makes her things even worse, because he makes her believe that she can´t live without him, and it becomes a "If you can´t stand it, I'll leave, and you'll be left alone."
You have to make it clear that you won´t endure that kind of behavior, and disrespect, and that it has completely broken your confidence.
You don´t have to be dragged by that kind of man, you must to leave him, and make it clear that you don´t need that kind of man in your life, even if it means living your life without him, that you were born without him, lived before know him, and you can continue living without him.
Only then, that type of men realize that what they are doing is wrong.
And they too can be abandoned.
And the last and most important thing, is because someone has betrayed you, does not mean that everyone, or the next person you fall in love with will betray you.
If you think that, it only means that the shadow of that man, persecutes you even in the present, and has not yet left your life.
Leave that shadow, and show that you can forget him.

wow..