Ioan Gruffudd/Instagram; Inset: Frazer Harrison/Getty
Evans, 50, reacted to the news in a now-deleted Tweet: "So it turns out that my husband, after two years of telling me I'm a bad person and I'm not exciting and he no longer want so to have sex with me and he just wants to be on set abroad...Has been in a relationship for THREE years behind all our backs. Good luck, Bianca."
One of Wallace's friends came to the Australian actress' defense tweeting that "I have personally known Bianca for years and they have NOT even known each other for three years let alone have an affair!!"
To which Evans replied that the friend was "spitting on the victim."
"You totally and absolutely know that they started seeing each other before he told me he didn't love me and wanted a divorce. If you want to get into this we can," Evans tweeted.
Reps for Gruffudd and Wallace did not immediately respond to PEOPLE's request for comment.
Donato Sardella/WireImage Ioan Gruffudd and Alice Evans
In March, Gruffudd filed for divorce from Evans after 13 years of marriage. The pair have two daughters, Elsie, 8, and Ella, 12. The two met on the set of their 2000 film 102 Dalmatians and married in 2007.
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The Fantastic Four actor's filing came a month after Evans posted a since-deleted tweet, saying Gruffudd had decided to end their marriage.
"My beloved husband/soulmate of 20 years, Ioan Gruffudd, has announced he is to leave his family, starting next week," Evans tweeted at the time. "Me and our young daughters girls are very confused and sad."
Toni Anne Barson/FilmMagic Ioan Gruffudd and Alice Evans
"We haven't been given a reason except that he 'no longer loves me.' I'm so sorry," she added.
Gruffudd did not comment on her tweets at the time. In a joint statement obtained by PEOPLE at the time, the two said, "As you can imagine, this is an incredibly difficult time for our family and we remain committed to our children. Thank you for respecting our privacy."
In February 2020, Gruffudd admitted to The Guardian that he and Evans have "struggled the past four years, making time for each other because physically we're apart."
"Alice had come back, she had been away for a week. I was showing off – 'the kids are in bed' – and she was [like], 'Yeah, you've done one week [alone], try six months,'" he said.