In 1979, Pol Pot and the Khmer Rouge were forced from power by the invading Vietnamese. Pol Pot officially resigned the leadership in 1985 but appears to have retained considerable influence.
Muscle fatigue. Muscle fatigue is the decline in ability of a muscle to generate force. It can be a result of vigorous exercise but abnormal fatigue may be caused by barriers to or interference with the different stages of muscle contraction.
However, when stress levels become excessive, they can easily cause fatigue. Stress and worry are two emotions that commonly cause tiredness. Stress can reach a point in which the sufferer flounders and is unable to see the light at the end of the tunnel, which leads them towards despair.