There are many examples of good mothers in these novels.
Wendy Torrance in The Shining will do anything to make sure that her son is safe and sound. Donna Trenton risks her own life to save her son from the massive dog in Cujo. Rachel Creed tries to Dave her relationship and changes her husband's mind in Pet Sematary.
There may even be more examples of good mothers than bad mothers within King's works.