I what way are you "hurting" your mother by discussing the idea. In what way is she being hurt? You are talking about this with strangers on an internet forum that has no clue who you or your mother is. You are talking with this with your therapist who may or may not know who your mother is depending on the situation where you live. However, said therapist already believes what she believes. So, how would your mother even know this is being discussed to be hurt?

Also, entertain is an interesting word. It is different than exploring. Maybe that is just a difference in how see the word. To me entertain has a feeling that you accept the assertion that X happened, whereas explore is more along the line of staying open to how your body responds to, what thoughts come to mind, and what feelings are experienced as you talk about what ever memories do surface.

For me, I questioned CSA because of several of my behaviors. At the same time not only do I not have memories of CSA, I don't even have memories of memories of CSA and I don't have any unusual amount of missing time/memories from my childhood. Still we explored this at my direction in trying to figure out some of my behaviors. I came out of it even more certain that there was no CSA in my childhood as I processed through some of my experiences and listened to what my body told me even if I didn't remember all the details of those memories.