By the way, I may mention I have found that, on those occasions when I do choose to answer a call, or must make one, using the speakerphone feature helps me greatly to feel less threatened. Holding a receiver to my ear, and hence allowing the other person to speak directly into my ear, seems to give the other person direct voice access into my brain, and I find it threatening. It as though that person is standing right beside me with their lips touching my ear. It creeps me out.
I think partly my aversion to phone usage is because in the past I not infrequently would get bullied over the phone by family.
But I have found that if I instead use the speakerphone, then when the other party speaks they suddenly become just a silly little tinny mouse-voice, while when I respond my voice resoundingly fills the room. I find it harder to be threatened by thin voice from a speakerphone; I can even turn down their volume to make them even less significant.