There are ways in which Henry's mother is traditional—for instance, she only speaks Chinese and is subservient to her husband—but she's still a caring and loving mother, too. Even when she follows her husband's lead and "disowns" Henry, she continues to do little things for her son so he knows she loves him:
After a few days, his mother did acknowledge his existence, in her own way. She did his laundry and packed him a lunch. But she did it with little ceremony, presumably so as to not go against the wishes of Henry's father, who had followed up on his threat to disown him figuratively, if not literally. (36.3)
Henry's mom doesn't agree with all of his decisions—in fact, she's as upset as his father is about his allegiance to Keiko—but she's not going to cut him off completely, either. She can be his mother, love him, and still see the world from a different perspective.