Sometimes saying the words out loud is a powerful way to clean out a wound. The secret, if it was one, is out. You are in control of the telling and someone else bears witness so you aren't alone with it. Even things we think we've dealt with can use airing out sometimes. There might be lingering feelings or stored anger -- these things come up when words are put to the feelings.

Sometimes we say stuff outloud and we realize that we really have come to terms with it. We are sad, or angry or whatever...but it doesn't overwhelm us for days. We've claimed our own history and we know pretty much why we are the way we are.

Your therapist is there to help you and to perhaps see things that you don't or can't. Telling about abuse might help her see why you do somethings, or react in certain ways. Or she might see some corners that still need cleaning out a bit -- so that the dust bunnies don't multiply and take over later. But do it on your own terms, when you are ready. No one should feel that they have to tell and it shouldn't feel like emotional voyarism.