"So Mrs Guinea had flown back to Boston and taken me out of the cramped city hospital ward, and now she was driving me to a private hospital"
Olive Higgins Prouty, on whom the character of Philomena Guinea is based, helped Sylvia Plath after her suicide attempt by paying for her treatment at McLean Hospital
in Belmont, Massachusetts, a prestigious and well-staffed private psychiatric unit which is affiliated to Massachusetts General Hospital.
Olive Higgins Prouty herself experienced some form of 'nervous breakdown' in her forties. In a letter to Sylvia Plath's mother* she commented that she felt 'better equipped to meet life' because of this experience.
The poets Robert Lowell and Anne Sexton, both of whom knew Sylvia Plath, also received psychiatric treatment at McLean at various points in their lives.
*Letters Home p.127.