Complex sentence: Broken by disappointment and disillusionment, she is killed as she accidentally slips from the windowsill where she is only contemplating suicide-and striking her head on the stonework, drowns unconscious, in the floodwaters surrounding the Castle.
Split into simpler sentences: Broken by disappointment and disillusionment, she is killed as she accidentally slips from the windowsill where she is contemplating suicide. As she falls, she strikes her head on the stonework, and drowns unconscious in the floodwaters surrounding the Castle.