Have to agree with everyone else here, these missions haven't been a failure because without the Falcon 9 (despite it being unsuccessful so far at landing) the 1st stage is designed to be disposable. The gutting part of this is that it happened before separation.
Each time they reach separation, they're doing no worse than before the Falcon 9 and when they do finally get it to land successfully, they'll have started saving money compared to previous 1st stage launchers.
Even now when I watch the videos of the attempted landing of the first two, despite knowing what happens, I still find myself willing that little thruster at the top to hold it upright before it finally gives out and tips over.
Try balancing a pencil upright on your fingertip, now imagine trying to do that using thrusters and a pencil the size of a rocket. The fact they've come so close is quite honestly astounding.
Chin up guys, you're doing great work, get to the pub, drink it off and try again.