Amber Portwood Speaks Out After Judge's Ruling Giving Custody of Son, 4, to Ex Andrew Glennon

Amber Portwood isn't giving up after ex Andrew Glennon was awarded custody of son James Andrew, 4, and granted permission to move the preschooler from Indiana to his family's estate in Malibu, California.

On Wednesday, an Indiana judge ruled that son James will move to California with his dad after a difficult and ongoing custody battle between the Teen Mom star, 32, and Glennon, a rep for Portwood confirmed to PEOPLE.

Portwood directly spoke out about the decision Thursday in a statement posted on Instagram. "I'm devastated and heartbroken by this outcome," the reality star begins."I've worked so hard to better myself and improve my relationships with my children."

Acknowledging her history of substance abuse and mental health struggles, Portwood notes, "a person should have a chance to redeem themselves and not be tethered to their issues from the past."

"People who've done therapy, and taken classes, and made efforts to change should not continue to be punished for past mistakes," she continues. "I've spent years rebuilding my bridges and did everything that was required of me, including completing 21 negative drug tests and multiple psychological evaluations."

Portwood concludes with a message of encouragement to others who may be struggling. "If your road has not been perfect, but you've worked hard to become a better, more stable and caring person today, keep moving forward," she urges.

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"[I'll] never stop fighting for my children who I love more than anything. I've been living in a nightmare for so long, trying to prove myself. I wouldn't wish this unbearable pain on any mother or father."

The new custody arrangement will see Portwood having overnight visitation for the first time since 2019. In order to introduce the preschooler to his new schedule, overnights will be phased into Portwood's time with James, which will alternate between Indiana, where both Portwood and Glennon currently live, and California, where Glennon will move with James to a family home.

Amber Portwood/Instagram; Andrew Glennon/Instagram

A source close to Portwood previously told PEOPLE that the MTV personality is "shocked by the judge's ruling."

"She loves her son more than anything and has always tried to be the best mother to him. She's not perfect, but this was a really dramatic thing to happen."

The insider added that Portwood is currently "contemplating what options she has to fight this," and feels frustrated after how far she's come.

"She's continuing to go to therapy to better herself and has done this consistently for three years straight," the source said.

Steve Granitz/WireImage Amber Portwood, Andrew Glennon

Glennon did not immediately respond to PEOPLE's request for comment.

According to court documents obtained by The Sun, though Glennon will now have sole legal and primary physical custody of James, the judge ordered him to "seek out and consider the mother's opinion before making any major decisions relating to the child's medical treatment, education and religion."

The court battle began in 2019 after Portwood was arrested for attacking Glennon while he was holding their son. The day after the incident, Portwood was charged with domestic battery, criminal recklessness committed with a deadly weapon and domestic battery committed in the presence of a child less than 16 years old.

In October 2019, Portwood was sentenced to two and a half years of probation, as well as court-ordered parenting classes. According to The Sun, Portwood successfully completed her probation — which included a 26-week Batterer's Intervention Program and over $1,000 in fines — and was officially discharged from probation in late April 2022.

Portwood went live on Instagram after news of the ruling went public Tuesday, sharing that she is dedicated to staying positive and exploring her options, also emphasizing the work she's done to better herself in recent years. The MTV personality, who is vocal about living with bipolar disorder and borderline personality disorder, also shared her belief her mental illness was "used against her."

In addition to James, Portwood also has a daughter, 13-year-old Leah, with ex Gary Shirley.

If you are experiencing domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233, or go to thehotline.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.