Elephants in the room need to be acknowledged. When there is something that obviously concerns you or distracts you, then it's important to mention it so that you can spend your time and energy on the reasons you are in therapy, not both of you trying to be polite and not say something that might make the other uncomfortable.

My T used to SI, but has said that she is "fully functioning" now, and it is pretty clear that she expects me to be past using that coping method by now. Not that she looks down on anyone for SI or other unhealthy coping methods. The first time I told her that I was a self-injurer (before I started therapy) she was very nice about it. Once I did start therapy, we talked about it more and she said at first that she couldn't ask me to give up SI entirely right then - only not to do anything requiring medical attention without contacting her first. So, she has been very understanding.

I like to glance at her scars when she wears short sleeves. It gives me hope that she knows where I have been because she was there too, and she found her way out. One time I noticed that she had new scratches on her arm. She saw me notice that, and told me that a cat scratched her, and she also said that I thought she had slipped (I was wondering), and that I wanted it to be true that she had. That was quite an interesting little confrontation. I probably would not have said anything out loud, and I am glad that she did. It needed to be acknowledged, or I would have kept on wondering, or maybe I would have created my own theories and stories about how and why she slipped, and if she did, then she can't say anything if I slip again at any time. I would have reasoned that I never have to really get better, because she claims to be better and there she is with a scratch on her arm. I would have created a delusion that I could use as an excuse forever.

If your T is a good therapist, she won't be a hipocrite. She won't lie to you, and won't expect something of you that she doesn't hold herself to, and she won't look down on you for what you do to cope. It's not likely that she SIed, but therapists are not immune to mental health problems by any means. Hopefully they commit themselves to the same standards of honesty, openness, personal growth, healthy coping, etc. that they ask of us. It is important for us to know that about them. While they should not use our time for their own need to talk about something, they also should model the openness that they expect of us, and not have secrets that they have to hide.