The other night, she said to me that she set her personal goal to "not being upset when I see my partner" - and admitted quite frankly that she doesn't like it, but understands that it's the right thing to do.
Not a realistic goal if left at that. Feelings just happen. You cannot choose how you feel or when you feel it. You can only choose how you behave in response to those feelings.
The success of a goal is partially in the stating because it helps give clues to what behavior to change, tells you what to DO. Her stated goal only tells her not to feel things and that is impossible. She will set herself up for failure if she leaves the goal at that -- to not feel something.
Perhaps restate more like
"My goal: Minimize my upset when I see my metamour / my spouse enjoying time with my metamour.
How I will do it:
(list the steps she will take.)"
My dad has mental health issues and he attends recovery group
to learn better coping skills. It's for ANY mental health issue from stress to anxiety to PTSD to... just anyone.
Here's their spotting worksheet.
I don't know if that would help her learn to spot herself? Or of checking if you have a local chapter handy?
Some things we can learn to do on our own. But some things need more help.