The American, stripped by cycling governing body UCI of his seven Tour victories in 2012 because of systematic doping, is supporting former England international soccer player and fellow cancer survivor Geoff Thomas in a fund-raising ride.
His presence on the same roads that will see the Tour pass through days later was described as "disrespectful and inappropriate" by UCI chief Brian Cookson in March.
"I'm that guy everybody wants to pretend never lived," the former US Postal team rider Armstrong said in an interview in the Daily Telegraph.
"But it happened, everything happened. We know what happened. Now it's swung so far the other way... who's that character in Harry Potter they can't talk about? Voldemort?
"It's on every level. If you watch the Tour on American TV, if you read about it, it's as if you can't mention him."
Armstrong, who is still fighting a lifetime ban and a $100 million lawsuit instigated by his former US Postal team mate Floyd Landis which he says would ruin him, said Cookson should be concentrating on more important things than his charity ride.
"But I do know that me and Geoff riding in France for this cause is the least of his problems," he said.
"If he is making public comments -- and this is as strong as I'll go -- he needs to be talking about other things because this sport is not in a good place for a variety of reasons."
Asked whether the recent Cycling Independent Reform Commission's (CIRC) report had drawn a line under the sport's murky past, Armstrong said it has been a wasted opportunity.
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He also criticised Cookson's record in tackling doping.
"What I hoped (CIRC) would achieve was that it would almost resemble some sort of adult conversation where we all just go: 'All right. Stop. This is really what happened. And this is who was involved and this is the line we are going to draw in the sand and this is where we are going to move forward.' But that didn't happen," the 43-year-old said.
"I came through on my end. I said I would be the first man in the door, I did it, went twice, answered every question. The thing comes out and it gets panned.
"So we haven't had that adult conversation, I don't think.
"I absolutely don't think (cycling's) in a better place."
On Cookson, he added: "You guys can decide if he has done a good job. Plenty of people would argue he's laid down on a lot of things.
"Whether it's expedited TUEs (Therapeutic Use Exemptions), Astana, Cookson is not very good at taking people down."
Image: Lance Armstrong
Photograph: Lucas Jackson/Reuters