There is drama and DRAMA and this manga belongs to the latter. Thia is a very interesting manga not one of all the chapters it has till now has been bad. Keep it up!!!
So, I guess they divorced because he was not paying attention to her or wasn't actually in love with her... makes me wonder why she agreed to marry him, then.
This manga is genuinely high art in a sea of mediocre romance manga. Motoi Yoshida is a god-level managaka when it comes to emotional investment in the characters.