Am I ready to talk about this in therapy? What if I’m not?

Im suddenly going much deeper in therapy than I ever have. I actually trust my therapist. Enough that I may talk about a part that has been showing up lately and making me feel a lot of shame and physical sickness. I have constant intrusive thoughts about the idea of talking about this very traumatic thing in therapy. To the point where sometimes I can’t sleep.

My hope is that if I bring it up and we explore it, even if it’s very painful, maybe I can stop ruminating and feeling so ill. But what if it makes it worse?

Does doing parts work help this kind of thing? I have been doing it for a while but this is the first time it’s felt visceral.