Bopara was painted as one of the villains of the piece when England blew a golden opportunity to win their first major international 50-over competition against India at Edgbaston in June.
Bopara and Eoin Morgan appeared to have a rain-reduced chase firmly in hand when they needed 20 from 16 balls with six wickets in hand.
But, following a 64-run stand that had rescued England from 46 for four, both departed from consecutive balls.
Bopara's dismissal lived longer in the memory when he carelessly picked out square leg to prompt England into a title-relinquishing panic.
"It is not something that is easy to forget," Bopara said.
"When you come that close to winning a major competition and you have the opportunity in your hands but see it just go, it is not a nice feeling.
"It sticks with you a while and I do still think about it now and again.
"I just hit a pretty good shot to the fielder standing at square leg.
"That is the way it goes. Luck was not with England that day.
"Oh well, it has gone now."
Bopara's role in the defeat was brought into closer focus because of his previous experiences of failing to complete a match-winning task.
"The key is you learn from those key moments in your career and life," he said.
"That was a key moment in my career and my life and you have to learn because before you know it there will be another one round the corner and you have to nail it."
While Bopara is focused on ensuring such slip-ups never again occur on his watch, he has not felt the need to re-live the experience in any closer scrutiny than his memory.
"I have not watched much of it on video," he said.
"Not ball by ball, just little clips of it. I don't see any reason to watch it through. I was there.
"I know more about it just by being there.
"You learn from it as a cricketer. You do not need a sports psychologist to teach you how to get over the line.
"Nobody can teach you how to do that. It is something you do naturally as a sportsman and athlete."
Bopara could get the chance to right any wrongs in his mind over the next three weeks.
England play their first 50-over match since the Champions Trophy against Ireland on Tuesday before embarking on a five-game series against Australia.
Those matches could also provide Bopara with a last chance to lay claim to an Ashes spot this winter.
The 28-year-old was overlooked for this summer's series but after Jonny Bairstow failed to lock down the number six position - the Yorkshireman was dropped for the final Test - a touring spot at the least appears open.
"I do (want to make that squad) but I know it is going to be a difficult task to break into that Test team now for the winter," he said.
"I have seen the selections over the summer so I know I have a long way to go. I won't give up.
"I am eyeing up some one-day cricket over the winter, maybe some T20s somewhere in the world. It is going to be an exciting winter for me."
Bopara could therefore end up in Australia regardless this winter, with the Big Bash League a tempting destination.
One man who faces a battle to join him Down Under is new Essex team-mate Monty Panesar, whose England future took an unlikely turn this month.
The spinner was released by his club Sussex after urinating on a bouncer at a Brighton nightclub, after which England opted to call up Simon Kerrigan for his debut at the Kia Oval.
Such was the difficulty of Kerrigan's first Test, however, that England's selectors may be reticent to take him into the cauldron of an Ashes in Australia.
Whether that offers Panesar a second chance is to be seen, but certainly Bopara believes he has begun life in Essex well.
"He has fitted in quite nicely," he said.
"He bowled really well in his first game. There were not many bad balls bowled.
"It shows what a quality spinner can do for a side. He gives you control. You know he is a good bowler who loves bowling and will churn it out for you."
Bopara was involved in Essex's decision-making before offering Bopara his loan deal, but admits he is not certain whether "churning out" the overs or returning closer to his family will benefit the Luton-born spinner.
"I don't know what it is going to take," he said.
"I only played one game with him but he seemed to be the same old Monty that I know.
"He is probably very happy the way he is right now.
"I don't know whether it is family or friends. Only he knows what he need to do.
"He will be fine and as long as he performs that is all we are interested in."