There is never an excuse for such a failure to take a backup but in early days keys weren't produced deterministically. They were randomly generated and they needed to take a new "digital" backup every time they created new set of keys which is what happens during mining (each block mined to a new address). Since the process was not as straight forward as writing down a mnemonic, it was easy for people to get lazy and not do it at all.
Even so, this is no excuse. If he had made at least one copy and kept it separate from the original location, the chances of avoiding this tragedy would have increased considerably. The wallet's keypool was updated every 100 transactions (both receiving and change addresses). When using the first 100 addresses, 100 new keys were generated.
He wasn't going to make more than 100 transactions in that period, so he would have been able to restore 100% of the funds if he had made a backup of the file.
As many have said here, he should give up and focus on accumulating bitcoins from now on (he should have accepted this in the first few months).
I know it's not easy, but unfortunately life is like that. We have to accept it and try to start over. Bitcoin is like a train that only passes through the station once... and that's what happened with Hames Howell's story. He grabbed onto the train, but didn't follow the safety rules, and that's why he fell. His story should serve as motivation for us users to follow basic digital security rules: backups and strong passphrases!
Finally He quits! James is done trying to find his lost drive.