Before listening to other people's comments and whining, you need to try the game yourself and find out why she hid it from her husband (Mc).
As far as I know, there is clear logic and meaning there, I'm going to spoil everything here, but in short, her ex-husband was an asshole who forbade the mother to see her daughter and even stole her daughter from her along with his gangs. I don't remember exactly, but that's what's there. In my opinion, she just didn't want to drag out her current husband until she understands whether Mc is a good man or not, or an asshole like her ex who ruined her life.