COMPLETE isolation is very harmful to mental health, there are thousands of studies which ALL (and that is quite unique in psychology!) agree that is a very harmful adn unwise to do it.
Everyone has their own levels of socialising (ex. extroverst Vs. introverts) but everyone need the human company
BUT total isolation is VERY HARMFUL.
IT'S VITAL FOR YOUR MENTAL HEALTH!
If you make yourself DO IT then don't!!
People who's been a long period of time isolated (ex. 2 or 3 years) then afterwards tend not to cope with social gatherings (which this affects jobs, family, love life, sex life, your children etc)
and also may cause severe mental illness, if you are in a very extreme isolation OR you are mentally prone to mental illness,- and trust me you don't want that!! (EX. paranoid/schizoid/schizotypal personality disorder).
(BUT - If you are like this, (ex. not wanting any social gatherings or avoiding them) then I strongly recommed to see a psychologist (i know they are not the solution - but it's the best we've got!)!
have a nice day...