Brooke Hundley, 22, filed the lawsuit on Tuesday in Stamford Superior Court, saying ESPN defamed her by firing her based on false statements by Phillips and by claiming she had not fully cooperated with its investigation.
Hundley, who was hired by ESPN in 2008 and paid $10.96 per hour, said Phillips made false statements to police in portraying her as a danger to his family and himself as an innocent victim.
She said Phillips falsely claimed he had been trying to end their relationship.
Hundley says she fully cooperated with ESPN's investigation and accused ESPN of acting maliciously to insulate itself from liability for Phillips' conduct.
Hundley, who is seeking more than $15,000 in damages, said she lost her job, subsequent job opportunities, damage to her reputation and has been harassed by the public as a result of the publicity.
ESPN said Hundley's claims are without merit and that its investigation found Hundley's characterization of the events inconsistent.
"Hundley's claims are without merit and we will vigorously defend against them," ESPN spokesman Josh Krulewitz said. "Her current charges do not accurately portray ESPN's handling of the matter."
Phillips acknowledged his relationship with Hundley.
His representative, Steve Lefkowitz, said Phillips was focused on getting his life and career back on track. Lefkowitz said he's known Phillips for more than a decade and said he would not lie to authorities.
Phillips and Hundley were fired in October.