Former sex abuser and her child husband explain the reason they are separating.

After 12 years of marriage to his former abuser, Mary Kay Letourneau, it was revealed yesterday that Vili Fualaau has filed for separation.

Today we know why.

Speaking to Radar Online, the 33-year-old DJ said he plans to become a licensed distributor of ‘Cigaweed’ marijuana cigarettes, which are legal in his home state of Washington.

“When you want to get licensed, they do background checks on both parties,” Fualaau told the outlet. “If I decide to be a part of it I have to be licensed and I have to be vetted and so does a spouse. She has a past. She has a history.”

That she does.

mary kay letourneau separating from husband
Mary Kay Letourneau and Vili Fualaau. Image: ABC.

The Seattle teacher - a then married mother of four - spent more than seven years behind bars for raping Fualaau, who was just 12 when the abuse began in 1996.

During their illegal relationship, the teen fathered two children, one of whom was conceived while his former teacher was out on parole.

In a move that attracted headlines around the world, the pair then married within ten months of her release in late 2004, and together raised their now-adult children.

Mary Kay Letourneau abused her student and future husband Vili Fualaau. (Image: ABC.)

As reported yesterday by TMZ, Fualaau lodged an application for legal separation from his 55-year-old wife on May 9.

But today he insisted they are still very much in love.

"It’s fine,” he told Radar Online. “A piece of paper doesn’t break someone’s feelings!”