Relationship between Takao and his mother

Yes, I would say that the lack of relationship between him and his parents, not just his mother, as his father seems to be absent too (if I remember correctly), is exactly the reason why he falls in love with the woman who seems out of reach, i.e. just like his parents. IMO, this film is about deep loneliness and our basic needs for a genuine connection, affection and love as humans.

The boy longs for someone who loves, cares and accepts him for who he is, who supports him and his dreams, but there seems to be a lot of sadness, anger and resentment behind his facade too. It's almost as if he's built a wall for protection telling himself, "I don't need anyone". The woman is in the same boat who is incredibly lonely and feels "pathetic and stupid" for the way she is when she's a grown adult at 27. When they meet, they're drawn to each other like magnets as if they'd seen themselves in the other person. But they're both coming from a place of lack, so neither has a room in their heart to give the very things they both want/need, e.g. connection, love, affection, acceptance, to the other. Self-fulfilling prophecy and a vicious cycle.

Both characters happen to be sweet and decent, but you can see how easily their life could've spiralled out of control for people like them in a similar situation. For example, if she seduces him and she ends up pregnant, so to support her and the baby, he gives up his dreams and starts working at 16, but the pay is low, so he ends up going down a dodgy path of crime to make ends meet. He gets arrested, goes to jail. She becomes a single parent, and so on and on.

Anyway, yes, when you think about why they're the way they are, it does indeed add another layer to the film and how some parents are quite selfish and shouldn't have had children.