desertion desertion /dɪˈzɝːʃən/

noun

1. () Withdrawing support or help despite allegiance or responsibility  ( abandonment , defection , desertion )
   withdrawing support or help despite allegiance or responsibility
    His abandonment of his wife and children left them penniless
   his abandonment of his wife and children left them penniless
   
2. The act of giving something up  ( desertion , forsaking , abandonment )
   the act of giving something up
     She felt a deep sense of abandonment when her best friend moved away without saying goodbye.
   She felt a deep sense of abandonment when her best friend moved away without saying goodbye.