Russell Hollins, who was headteacher at Royal Wolverhampton Junior School in the 1980s, tried to get his victim sacked from her job as a teacher in Warwickshire and made false allegations of sex abuse against her children.
He sent a deluge of messages and used different names and numbers to carry on contacting her when she blocked his phone number and social media profiles.
Exeter Crown Court heard that he had already been convicted of stalking other partners and had seven previous convictions for breaking restraining orders.
Hollins, now 71, targeted his victim's family when he could no longer get to her directly and carried on his campaign of hate after he was arrested and served with a non-molestation order.
Some of his messages were pleas for her to restart their relationship, including one which offered her £25,000 to live with him again.
Others were threats or insults which humiliated and degraded her.
He even went to her home where he uprooted pot plants and scattered rubbish around her garden before almost running over a concerned neighbour who tried to photograph him at the scene.
Hollins had only been in an on-off relationship with her for a year but became obsessed with his victim and set about controlling her life.
She told police he was manipulative, intellectually arrogant and a misogynist who despised women and thought them inferior to men.
He was being treated for prostate cancer at the time he broke up with her and used this to exercise emotional blackmail on her, persuading her to attend hospital appointments with him.
Kelly Scrivener, prosecuting, said the stalking started in June last year after the break-up.
A non-molestation order was imposed in September last year, but his campaign continued until his arrest in May.
Seven years in charge in Wolverhampton
The court heard that Hollins had spent his working life as a well-respected teacher and was head of private or state schools in Wolverhampton, Cornwall, Yorkshire and Warwickshire.
When Hollins left Royal Wolverhampton Junior School in 1988, the Express & Star reported how the married man with two children was leaving to work in Cornwall after seven years in charge.
His teaching career ended because he was convicted of stalking his ex-wife and another partner in 2009, 2010 and 2015.
Ed Bailey, defending, said Hollins is now ashamed of his behaviour, which has ruined the reputation which he built up over a lifetime of service in education.
Hollins, of Strand Court, Topsham, and formerly of Shakespeare Gardens, Rugby, admitted stalking and breaching a non-molestation order and was jailed for two years by Judge David Evans at Exeter Crown Court.
"You have caused her very great distress and damaged her life," the judge said.
"The stalking was clear evidence of some sort of inflated self-regard. You had a sense of entitlement and an expectation of subservience from her. The messages were cruel.
"She was the third woman who you have harassed over the past decade. This was a sustained course of quite deliberate behaviour."
The judge also imposed an indefinite restraining order banning any contact with the victim, her employers, or family and barring him from going to a large area of Warwickshire around Bulkington, Bedworth and Coventry.