Complex sentence: He values his freedom to travel and socialise and unabashedly confesses that he has "no room, mentally or emotionally" for his niece and nephew, who were orphaned and left in his care as infants, and whom he keeps at Bly, his country estate.
Split into simpler sentences: He values his freedom to travel and socialise and unabashedly confesses that he has "no room, mentally or emotionally" for his niece and nephew. They were orphaned and left in his care as infants, and he keeps them at Bly, his country estate.