Idea from here.
It’s not common knowledge that those with schizoid personality disorder experience splitting because this personality disorder is under-researched. But people with a personality disorder have at least some form of splitting due to not having whole object relations.
Object Relations: This is the ability to form an integrated, realistic, and relatively stable image of oneself and other people that simultaneously includes both liked and disliked aspects and also strengths and flaws. If you do not have whole object relations, you can only see yourself and other people in a split and un-nuanced way as either all good or all bad. It is as if you had to sort all your experiences with yourself and other people into only two buckets: the all-good bucket or the all-bad bucket.
The Split Object Relations of Three Personality Disorders:
Borderline: “I’m loved” or “I’m hated”
Narcissist: “I’m admired” or “I’m garbage”
Schizoid: “I’m controlled and tolerated” or “I’m alienated and exiled”