The movie and the book 'The Neverending Story' don't really focus on naming Bastian's mother. It seems that the story is more centered around Bastian's adventures in Fantasia rather than his mother's name or her own story. So, unfortunately, we don't have a name for her.
Sorry, I don't know the mother's name off the top of my head. Maybe it's mentioned in a specific chapter or part of the story that you could re-examine.
The Neverending Story doesn't disclose the name of the mother. It's a story that is rich in fantasy elements like the different lands in Fantasia, the characters like Atreyu and Falkor, and Bastian's journey of self - discovery. But when it comes to his mother, the story leaves this aspect blank, not providing any name for her.
I don't think the mother's name is important in The Neverending Story. The story is centered around the adventure in Fantasia, the hero's journey, and the power of imagination. The mother is likely just a background figure, and her name not being given doesn't detract from the overall narrative.