How do I prove excessively vicious conduct or cruelty of treatment?

Cruelty of treatment and excessively vicious conduct are two
distinct grounds for divorce, however, they mean essentially the
same thing.  As a result, they are often listed together.

A limited divorce is available on these grounds, however, cruelty of treatment and
excessively vicious conduct are rare.  The typical poor treatment of which
spouses commonly accuse each other as a marriage disintegrates rarely arises to
a level sufficient to prove these grounds in court.  Typically such grounds
require substantially more than disagreements, emotional isolation, arguments,
shouting, and even an occasional incident of physical violence.  These grounds
generally require a condition that is closer to routine and deliberate mental or
physical torture by one spouse against the other or against a minor child of the
complaining party.

In addition to a limited divorce, these grounds also serve as
grounds for an absolute divorce.  In order to obtain an absolute divorce
on these grounds, in addition to the above, a party must also show that
there is no reasonable hope or expectation that the parties will reconcile.