First stage DOUBT: frustration, burnout, or simply unhappiness with an accustomed status and the roles associated with the group or relationship. 

Second stage SEARCH FOR ALTERNATIVES: you may think about or start planning for separation.

Third stage ACTION OR DEPARTURE: a clear turning point makes you feel it is essential to leave. 

Last stage: CREATION OF A NEW IDENITY: form new connections - who do you want to be? 

Adjusted from Helen Ebaugh's Becoming and Ex