Complex sentence: But her happy life end with Nolan beat Mark to within an inch of his life, suddenly stopping just short of death and then fleeing the planet, but before fleeing Nolan said he never loved her but used her to sired a son, Mark.
Split into simpler sentences: But her happy life ended when Nolan beat Mark to within an inch of his life and fleed the planet. Before fleeing Nolan said he never loved her but used her to sire a son, Mark.