I think the language Stephanie chooses to use about her experience is important.
She mentions 'the trans widows who have been abandoned or abused by trans ex-husbands' at the start of the article. These are other women. She does not see herself as a trans widow.
This was also mentioned in Janice Turners article.
Stephanie, feisty and tough, balks at the idea she is a passive victim, a “trans widow”. “I feel sad at times, but I’m at peace and Debbie is so much happier.”
Stephanie seems to think that being a trans widow, or even believing that Debbie has been abusive, makes her a victim. She doesn't want to see herself as a victim, which is understandable, because for her this word implies weakness and passivity. She says that she has made her own choices. This is what she believes or wants to believe, even though she is only 'at peace' while Debbie is happier. But is she also happier?
But none of what Stephanie says or believes means that Debbie is not abusive. This says nothing about Stephanie, her reactions to Debbie's actions or her beliefs about her own situation. Abusive behaviours are abuse, no matter what the effect on the victim or how they feel about it. (I've been trying to think of another word rather than victim, which Stephanie would reject, but I can't think of one.)