I found CBT + Exposure super helpful in dealing with specific anxiety. Anxiety is irrational but can't be reasoned away. I only talked to my therapist for 30min once a month. I just kept going through the steps: (a) predicting how much many things would bother me, (b) tackling something that would bother me but not too much, (c) if I felt stuck, checking what negative thought pattern I was using. The 30min sessions basically helped keep me at right-level challenges, and sometimes break down the biggest challenges into more meaningful pieces. It's the best therapy I've ever done. If you can't force yourself to do something you know you want to or should do it could be helpful.
I found talk therapy was more helpful for complex topics. E.g., your attempts to demonize your STBXW would be effectively challenged and you'd gain more perspective. In my case, it helped me overcome *some* childhood trauma by reviewing the incidents with new eyes. Sometimes, a child believes they have more power over a situation than they actually do.
I have not found my ideal treatments for childhood trauma or basiphobia yet.