Use the XEvent files captured in the LOG directory to confirm that a DDL command was not issued.
There are protection mechanisms built into the AlwaysOn Availability groups to protect the data. In this specific case I had the registry on Node 1 become damaged. In doing so the cluster registry no longer matched the SQL Server metadata and my AG is removed from the node.
Note: The database(s) still exist on Node 1 but they are no longer joined to the 'My AG' availability group.
This protects the data on Node 1 from unexpected/mis-configured changes.
It is recommended that you keep the following backups for proper restore of the Availability Group configuration.