Bronwyn Ingram, once described by Filner as "San Diego's first lady," said she broke up with Filner after noticing "behavorial changes in Bob that rendered him, in my opinion, less than optimally effective as mayor."
But since resigning, she wrote, he "has taken the responsibility of healing himself as seriously and with as much determination as he displayed throughout his life."
Ingram mentioned Filner's experience as a Freedom Rider during the civil rights movement in the South.
Filner's two ex-wives and his son also supplied letters to be considered by Judge Robert Trentacosta. Letters of support were also written by a Baptist minister and a San Diego lawyer now married to one of Filner's ex-wives.
Trentacosta on Monday accepted the major terms of the plea bargain, sentencing him to 90 days of home confinement with no jail time.
Filner pleaded guilty in October to a felony charge of false imprisonment and two of misdemeanor battery, all involving women. He had resigned Aug. 30 amid accusations from nearly two dozen women of sexual misbehavior.
Under terms of the plea bargain, Trentacosta ordered Filner to serve 90 days of home confinement starting Jan. 1. He also reduced his city pension and fined Filner approximately $1,500.
The judge placed Filner on probation for three years. If he violates probation, he faces jail, the judge ruled, adding that Filner cannot seek office during his probation.
While on probation, he will wear a GPS monitor so police will know if he leaves his home for anything except for medical appointments, religious services or court appointments.
The probation report said that Filner is undergoing counseling and is taking medication commonly prescribed for depression, anxiety and mood disorders.
While in Congress, he was seeing a psychiatrist and had prescriptions to stabilize his moods but once returning to San Diego to run for mayor, he stopped taking the medications, according to the report.
Filner's attorney, Jerry Coughlan, told reporters after the sentencing that there is a "medication issue" to help explain Filner's behavior in his months as mayor.
None of the three victims, listed only as Jane Does 1, 2 and 3, opted to make a "victim's impact statement." If the victims request restitution for damages, a hearing will be held, Trentacosta said.
In a brief statement, Filner offered an apology to his family, staff, supporters and to "the women I have hurt and offended."
The 71-year-old Democrat said his misbehavior toward women "will never be repeated." He said he will work to regain the public's trust.
"I look forward to making further contributions to the city I love," Filner said.
The prosecutor, Deputy Atty. Gen. Melissa Mandel, told Trentacosta that Filner's actions offended and demeaned the three victims and hurt San Diego. She said some of the victims had come to meet Filner to discuss public issues and instead were treated disrespectfully.
Filner used "the power of public office" to demean and scare women. "Filner sold himself to voters as a champion of civil rights" but his actions showed him to be different, Mandel said.
In the felony case, Filner grabbed a woman in a headlock. In the misdemeanor cases, Filner kissed one woman and grabbed another on the buttocks.
Ingram, in comments made before the first woman accused him of sexual harassment in July, had told reporters that she had broken up with Filner after catching him making dates with other women and acting in a volatile manner.
Outside court, attorney Gloria Allred blasted the plea bargain as too soft. She said Filner should have been prosecuted under a felony law, sent to prison and made to register as a sex offender when released.
"Your freedom is a gift you do not deserve," said Allred. She represents former Filner aide Irene McCormack Jackson in a sex harassment civil suit against Filner. A hearing is set for January.
Filner was elected a year ago to succeed termed-out Republican Jerry Sanders. He was the first Democratic mayor since Maureen O'Connor, two decades ago.
Almost immediately, Filner's brusque, confrontational style caused controversy at City Hall. He proclaimed repeatedly that he meant to shake up what he saw as an entrenched power structure that catered to the interests of a downtown business clique.
He feuded with City Atty. Jan Goldsmith, a Republican, over issues involving marijuana, seals on the beach at La Jolla and a controversial case charging a graffiti sloganeer with vandalism.
The conservative editorial page of the local newspaper blasted nearly his every move and ridiculed him in cartoons.
In July, when the first accusations of sexual harassment became public, it took only six weeks for Filner to be forced into resignation.
In the beginning, Filner sought to survive the controversy by admitting his behavior had been wrong and enrolling in a therapy program. He vowed to return to City Hall and be "the best mayor I can."
In a resignation speech Aug. 23, he was alternately sorrowful and defiant, taking responsibility for his misbehavior toward women but then complaining that his political enemies had fueled a kind of lynch-mob mentality in the press and public. His resignation became effective Aug. 30.
The charges were brought by the state attorney general's office. Dist. Atty. Bonnie Dumanis had bowed out of the case, citing a conflict of interest; Dumanis had been eliminated in the 2012 primary race for mayor.
Although the sex harassment accusations — in the media and later in the criminal complaint — may have been a shock to the public, Filner's abrasive behavior was not.
During three decades in public life, on the school board, City Council and then 10 terms in Congress, he had acquired a reputation for being dismissive toward opponents and difficult for nearly everyone.
During his race for mayor, he explained that his hard-driving style was the product of his passionate approach to politics as a way to improve the lives of the less fortunate.