SQL Server Database Mirroring is going to die. How can I guarantee high availability now?
As noted, mirroring is not dead.  (At least not yet.)  The general population doubts that Microsoft would totally abandon HA for Standard Edition.

However, there are other methods.  In the SQL Server 2012 documentation when referring to mirroring it says: "If your edition of SQL Server does not support AlwaysOn Availability Groups, use log shipping." 

http://technet.microsoft.com/en-us/library/ms143729.aspx

There is plenty of instruction on using log shipping.  

EDIT: You might read Kin's links at: SQL Server Log Shipping: File copy options?