noun (n)

• the termination or disintegration of a relationship (between persons or nations)(noun.act)

  Synonym:
  dissolution
  

  source: wordnet30
• coming apart(noun.event)

  Synonym:
  detachment, separation
  

  source: wordnet30
• Disruption; a separation and dispersion of the parts or members; as, a break-up of an assembly or dinner party; a break-up of the government.(noun)

  source: webster1913