Robert McNaughton, 51, from Halesowen, set up fake Facebook accounts to troll the woman, West Midlands Police said.
The force said he was "hell bent" on destroying her life after she spurned his reconciliation attempts.
McNaughton, of Tenter Drive, was convicted after a trial of conspiracy to commit criminal damage.
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Sgt Chris Jones said: "McNaughton could not handle being rejected and became hell bent on destroying his ex-partner's life."
During December 2014 and February 2015, he bombarded her with abusive Facebook messages, threatening to release intimate images.
He also hired two men, Matthew Barker and Joden Smith, to carry out a string of attacks on her home, culminating with her car being set on fire in February 2015.
Barker, 44, of Leicester, admitted conspiracy to commit criminal damage and was jailed for 43 months.
Smith, 20, also of Leicester, admitted conspiracy to commit criminal damage and arson, recklessly endangering life and was sentenced to four years at a young offenders institution.
The men were sentenced at Wolverhampton Crown Court on 31 March.
A man who began a hate campaign against his ex-partner, which culminated in her car being petrol bombed, has been jailed for five years.