It could be that while you found a therapist that you feel safe with, you have just been able to get a certain amount of safety and you don't know how to even begin going any deeper, it has a lot to it and often just the thought of trying to break the ice on it is tiring.

How I managed to get past that is to first bring up the topic in a conversation so I could see how my T responded. I used some example of what I read here in the forums and how I was moved by certain stories. That is when my T talked about CSA and he was quite knowledgeable about it and that allowed me to add in a little bit of myself to let him know I had experienced things myself. I kept our conversation mostly about the overall subject so I didn't have to dig too deep into it and had some time to think about it.

You don't always have to approach your secrets with telling them, you can choose to just discuss the subject first. Whatever you have experienced, believe me, you are not alone and a good therapist knows to go slowly with these kind of challenges their patients struggle to discuss. You don't have to get graphic either, what is important is understanding that part of your life better, something you probably set aside but have challenges with that you never felt comfortable talking about.