On Mental Health Facilities

Solid information can be found at Mental Health America’s website.
MHA is a nonprofit dedicated to supporting mental health since 1909. Originally named the National Committee for Mental Hygiene, it was founded by Clifford Beers, who suffered an episode of bipolar disorder for which he was institutionalized. The abusive treatment he experienced and witnessed moved him to write a book and then found this organization, to advocate for reform.
The site assumes patient agency, where hospitalization serves for stress reduction, to take time for accurate diagnosis and medication:
In-patient care is not designed to keep you confined indefinitely; the goal is to maximize independent living by using the appropriate level of care for your specific illness. 
But also notes:
There are also times when a person becomes so ill that they are at risk of hurting themselves or others and hospitalization becomes necessary even though the individual does not wish to enter a hospital. While seeking help voluntarily is always preferable, a family member may have to make the decision to hospitalize someone with a mental illness involuntarily. This act, while difficult, can be more caring than it seems if that is the only way to get someone the care they need, especially if there is a risk of suicide or harm to others. A family member should consider working with their relative who is at risk of a mental health crisis if they would like to create a Psychiatric Advance Directive during a time when they are well. 
(Later)
Your treatment options depend on the level of care you will need to receive. Who administers that care depends on where you go to seek treatment. Listed below are several different types of facilities that offer different levels of care:
  • In-patient, 24-hour care is provided by the psychiatric units within general hospitals, and also at private psychiatric hospitals. Care is supervised by psychiatrists, and provided by psychiatric nurses and group therapists.
  • Each state has public psychiatric hospitals that provide acute (short-term) and long-term care to people without means to pay, those requiring long-term care, and forensic patients.
  • Partial hospitalization provides therapeutic services during the day, but not on a 24-hour basis. It can be an intermediate step between in-patient care and discharge.
  • Residential care is 24-hour psychiatric care provided in a residential setting for children or adolescents, or residential programs for the treatment of addictions.
The site provides a number of FAQs and links for more information.