4.4.1. Remonstrate privately with a colleague if that colleague appears to be engaging in unethical behaviour; where this action does not resolve the issue, they shall bring the matter confidentially and without malice to the attention of the Association's Complaints Committee.

Have you already taken the first step to approach the colleague before reporting with attempt to resolve the issue privately already? How did that go? Sorry you are in this tough predicament. The only behavior you are responsible for changing is your own. Not your t's. It's kind of you to take her feelings into consideration and I know having to deal with this is very difficult. When you really look at the big picture, you are hurting her more by doing nothing. She's self-destructing...at least with her career. Confronting privately may force her to deal with her cognitive deficit, whatever that may be. And taking action will hopefully empower you. Did you have to report your ex-t?