George was obsessed with IT salesman Colin Blanchard, telling him she was his "paedo whore mum" and sending him eight pictures a week, Bristol Crown Court heard.
Mr Justice John Royce described the evidence as "chilling" as he heard how George and Blanchard discussed practices like rape via text.
In one message, George referred to herself and Blanchard as the "perfect paedo couple".
George put her hand to her eyes as the facts of the case were read out in court, apparently shielding herself from the gaze of parents and her own husband.
George and former prostitute Angela Allen were sentenced at Bristol Crown Court for a string of sexual assaults and making and distributing indecent images of children.
Mother-of-two George, who worked at Little Ted's Day Care Unit in Plymouth, and single mother Allen, from Nottingham, carried out the offences with Blanchard, from Smithy Bridge, near Rochdale, after they all met on Facebook.
George, 39, previously admitted seven sexual assaults on children and six counts of distributing and making indecent pictures of children.
Blanchard, 38, a father of one, pleaded guilty to 17 child pornography counts and two sexual assaults on children. He also admitted a further charge of possessing extreme pornography.
Mother-of-one Allen, 39, pleaded guilty to four child sex assaults and one count of distributing an indecent image.
Mr Justice Royce gave George and Allen indeterminate sentences for public protection today.
Blanchard's sentencing has been adjourned as he may face further charges, the court heard.
The abuse began in September last year and carried on until this June.
George, Allen and Blanchard subjected their young victims to humiliating sexual abuse, some of it involving plastic golf clubs, sex toys and toothbrushes.
They never actually met in person, recording the abuse on their mobile phones and exchanging the pictures via email to unprotected accounts including MSN Hotmail.
The judge told George she would serve at least seven years in jail before she could be considered for release. Allen was told she must serve at least five years.
But Mr Justice Royce warned them they would only be released if they no longer posed a threat.
There was a shout of "yes" from the public gallery as he warned them that otherwise they faced "the rest of their days behind bars".
The judge said: "This case has cause widespread revulsion and incredulity.
"It has rocked the city of Plymouth but the shockwaves extend much further, perhaps to every nursery school in the country."
He told George: "You gave parents who entrusted their children to your care every reason to believe they would be safe.
"How grossly did you abuse their trust. What you did plumbed new depths of depravity."
There were gasps of horror from the public gallery as details of Allen's abuse were recounted by the judge.
Prosecutor Simon Morgan had earlier described how George, an apparently caring nursery worker, became obsessed with sex.
As her behaviour grew stranger, she had even commented to a child's father that his boy was "well-endowed".
After meeting on the Facebook dating site 'Are YOU interested?', she started to send Blanchard a stream of abuse images and texts.
Mr Morgan said: "Witnesses believed her sexual boundaries had blurred. It was as if she wanted to do anything to please Blanchard."
After George's arrest, she told police: "I'm disgusted with myself. I can't believe what I've done. I love children."
She then corrected herself and said: "I love working with children."
George admitted texting Blanchard regularly on a mobile she called her "fun" phone, adding: "It doesn't matter what I say now. My job is gone, my family is gone."
George had joked that Blanchard was a "dirty paedo". He joked back that she did not need "grooming" and that the perversion was inside her, ready to come out.
Over a thousand contacts were logged between them, Mr Morgan said.
Colleagues said George, a qualified special needs co-ordinator, "seemed to become vulgar", constantly talking about sexual topics.
Personal phones were not allowed in the nursery - George was once told off for having one - but rules were "relaxed" because the in-house phone was unreliable.
Mr Morgan said that in police interviews the defendants tried to blame each other.
George told police that in February, Blanchard had asked for pictures of children "as he knew where I was working".
She said: "Immediately I knew what sort of pictures he wanted. I sent him two or three when I was changing their nappies.
"I knew it would make him happy. I felt disgusted but I did it anyway."
She added: "I couldn't trust him, so to make him happy I just sent him more pictures."
She said: "It was just random - if he wanted extra pictures I'd take them."
She said she had taken pictures of babies as it was "easier".
Mr Morgan said she had taken "about eight (pictures) a week".
Later Blanchard told George he had found another woman (Allen), who was "really dirty, filthy", the court heard.
Staff at Little Ted's said they felt "betrayed" by George's actions and one said that "a lifetime of childcare had been ruined by Vanessa's actions", the court heard.
Defence barrister Nicolas Gerasimidis said George was "caught up in a double life" where she both cared for children and was abusing them.
George was of previous good character and got no sexual gratification from what she did, he added.
Counsel for George and Allen said both were vulnerable and eager to please.
They claimed the majority of the pictures showing objects penetrating their victims were staged.
Blanchard had promised them love and attention and a future together, and manipulated them to serve his sexual needs.
But Mr Justice Royce said George's barrister had made her abuse sound as forgettable as "a cup of coffee".
The judge had urged George to identify her victims at a previous hearing but Mr Morgan said today that she had declined further police interviews.
A document had been drawn up by George and her defence team giving more details of potential victims, the court heard.
But Mr Justice Royce said that although George had given an unspecified number of victims' names, there were so many doubts about other details it was not possible to identify the children accurately.
He said: "It would be quite wrong for the crown to tell parents that their child had been abused if in fact that was not the case.
"I find it difficult to accept that she is genuinely not in a position to provide more information than she has."
