When Buddha spoke about suffering,
he meant that we have unsatisfactory experiences.
Even the happiness we have does not last forever,
and that situation is unsatisfactory.
The causes of our problems lie not
in the external environment and those inhabiting it,
but in our own mind.
The disturbing attitudes and negative emotions,
such as clinging attachment, anger, and ignorance,
are the real source of our unhappiness.
Original post found here.