Solitude is lack of contact with people.
never heard of it before
Oh ok, it's a state of being lonely.  It can be caused by bad relationships, loss of loved ones, deliberate choice, infectious disease amongst others
do people go to counseling for it?
Solitude
Solitude is a state of seclusion or isolation, i.e., lack of contact with people. It may stem from bad relationships, loss of loved ones, deliberate choice, infectious disease, mental disorders, neurological disorders or circumstances of employment or situation (see castaway).
Short-term solitude is often valued as a time when one may work, think or rest without being disturbed. It may be desired for the sake of privacy.
A distinction has been made between solitude and loneliness. In this sense
easily through the coughs and sneezes of infected people. It may also be spread through direct contact with mouth or nasal secretions. Nine out of ten people who are not immune and share living space with an infected person will be infected. People are infectious to others from four days before to four days after the start of the rash. Most people do not get the disease more than once. Testing for the measles virus in suspected cases is important for public health efforts.
The measles vaccine is effective at preventing the disease