This is a similar situation but very different at the same time. I came out to my therapist inadvertently; I am open with my sexuality (I am a cis lesbian) and don't try to hide it. I, in passing, mentioned that I had gone on a date with a girl and she was like, "Wait, are you gay?" and I just said "yes lol" but she kept pushing. "Why haven't we talked about this before? Do we need to dig deeper into that?"
I told her no. I don't have any gay trauma (I know I am very lucky for that). There is nothing to dive into; nothing to analyze. I am gay and I am at peace with it. When I told her that, she understood and did not bring it up again.

I think if you are able to be straight with your therapist, that's the best decision. I agree with junkDNA's response.