I would say something along the lines of "I divorced your brother, and now I would like to formally divorce you."
Juntúul koʼolel periodista, yaʼab baʼaxoʼob u yojel yoʼolal le divorciooʼ, ku yaʼalik: "Beoraaʼ yaan u kʼexkoʼob baʼaxoʼob suuk u beetkoʼob yéetel yaan u kanik u aktáantoʼob tu juunaloʼob le problemaʼob kun antaltiʼoboʼ."