While her actions point to the soft "Ch", imho, I'd recommend her adopting the hard "Ch", if at all possible.
She seems like the type to hang with those familiar with urban slang, rather than the OED crowd.
My guess is that this had a history and that the diss of Chartaya towards Mama wasn’t the first move in this chess game of hell.
If the guy will stand up and be a real man he could make peace, but it would involve getting that Motherzilla out of his life.