Willhelm's mysterious past

Past events leave a permanent mark on all of us. Absoulutely everything. Even things we don't remember. This book takes place in very little time, but if there's something that we can realize quickly is that Willhelm had a happy past life, and he lost it because of some stupid mistake. He's notproud of his life, but he does talk about some woman named Margaret all the time and about his kids. It would be interesting if the story of Willhelm's past was told, however it's also interesting to imagine what happened. They got divorced, which is obvious, but why? And why did Willhelm go to NYC after the divorce instead of at least staying in the same city as his children's? He does miss them a lot, so I don't understand why he left them. Willhelm's father tells him earlier that he gives too much money to the kids, but we don't know that, since we don't know how the kids live, We don't even know how many kids he has and what ages they have, and we don't know if they're boys or girls. The story is about Willhelm, but his past should be mentioned as well, and it isn't, as if the author was trying to tell us that Willhelm is trying to forget about his past.