You are going to the T to help YOU, not her. If she's cross, she's cross -- that's her lookout. I hope you can find some way not to let that impact you (much) although I know that's hard.
Guilt is a tough one. I deal with that, too.
It does sound as if the T is trying. . .in addition to being "trying" sometimes. I does seem nice that she reached out -- didn't have to do that. I can understand your being apprehensive somewhat, though . . .can you identify what about her causes the apprehension besides what you mentioned? Certainly her seeming dismissal of your feelings and concerns sometimes. And your concern about her possible anger. Anything else?
Hopefully the appointment will go well. Please let us know.