Anyone who has been through what you are going though feels the same way. I lost 9 of 12 fish last month to Velvet. I kind of knew something was not quite right with two of the fish prior to my "Black Sunday" but my fish were super healthy and fat for 7 years so I figured I would give it a while to clear up on its own. To make matters worse, I didn't even look into fish disease to brush up on symptoms or treatment. When Sunday came around I had no medication except antibiotics and Prasipro on hand. A few fish were already dead and the rest were on deaths door. I referred to this forum often and spent the day doing what I thought was the best I could for the fish. I made a few HT/QT mistakes which may have played a roll in at least a few more fish deaths. It's hard not to feel responsible when your fish rely on you for everything and then everything goes wrong. You've got a better handle on your situation than I did. You should be proud of the way you have handled it so far.
Plus think of how many you saved out there for those of us reading this and making sure we are stocked up on all the meds. I wrote scripts today to get some Metro and CP stocked.