But they weren't the only ones who chose to speak out on Instagram that day, as T.J.'s wife, Marilee Fiebig, also snuck back onto social media following months of silence.
While Marilee - who was married to T.J. for 12 years until news of his romance with Amy was made public in November 2022 - wasn't quite as defiant in her return, it was somewhat fitting that it was done at the same time as her estranged husband.
Marilee's personal feed has remained untouched for four months, but she chose to comment on a post by Axis Hats New York, who she is working on a new venture with.
The company posted a gratitude post, thanking everyone for their help in launching and expanding their business over the last few months.
They said that exciting things were headed their way and Marilee chimed in with a comment. "Let’s go," she wrote. "This is amazing and so excited for all to come."
It's refreshing to see the attorney in seemingly good spirits, since it's been a difficult period for her and her daughter, Sabine, who she shares with T.J.
Marilee first addressed the affair with a statement through her attorney, Stephanie Lehman. It read: "During the holiday season and in light of the challenging times, Marilee's sole focus has remained on the overall best interest of her [10-year-old] daughter.
"To that end T.J.'s lawyer and I have been working together to move their divorce forward privately, expeditiously and as amicably as possible."
She spoke out against T.J.'s conduct regarding the matter, adding: "Notwithstanding, we continue to be disappointed by T.J's lack of discretion, respect and sensitivity toward Marilee and the party's daughter."
Amy's divorce from her husband of 12 years, Melrose Place actor Andrew Shue, has been finalized, while T.J. and Marilee are reportedly still working through negotiations in court.
The former GMA3 co-hosts shared the same picture focusing on their sneakers on Monday.
The image was taken during their training session for the New York Marathon – which is set to take place on Sunday November 5.
It's their first joint post since the became a couple and it also appeared to finally confirm their relationship status.
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