Please... We don't need this shitty forced drama here. We don't need to make MC more unlikeable than he already is.
What's the problem anyway? Mom is absolutely fine without him and has a lot of relatives, she can easily manage this small local shop by herself for the next 10 years. She is what, around 45-50 y.o. at beast and pretty healthy as well. And Kaoru is 18 soon, he doesn't need mommy to take care of him.