Divorced mother meet her son, then her two other kids, at the end she dies in car accident

Mother's Boys (1994)
IMDb synopsis:
Jude Madigan (Jamie Lee Curtis) abandons her husband, Robert (Peter Gallagher), and her three sons without any explanation. Three years later, Jude inexplicably returns to reunite her family. However, Robert and his new lover, Callie (Joanne Whalley), see Jude for the true psychopath she is and try their best to protect the boys. Jude embarks on a non-stop stalking and harassment campaign against the family and even seduces her eldest son, Kess, into committing acts of violence.

Mother's Boys (1994) - IMDb