My thirty-ish older two adult children were in town for a family event, and I took the opportunity to have The Talk with them today.
Just to make things interesting, I had previously been explicitly forbidden by my spouse from revealing anything about my true nature. I was under strict instructions to repress myself, present only as male, and never discuss my being a transsexual person with them.
Oops.

I originally planned to go over this with both in the evening after my spouse had gone to bed (8:00 PM as usual). My daughter was going to be out overnight at an old friend's though, so I decided to tell her when the opportunity presented itself and then tell my son later.
When my spouse headed upstairs with my son to chat, I took the opportunity to talk to my daughter at once. We closed the guest room door, and I told her I had something important to tell her that my spouse had forbidden me to talk about, but I felt she had to know.
First, I am not dying. I don't have a fatal disease, nor am I running away with someone. I do have a medical, psychological, and ethical problem I wanted to tell her about. I told her about my depression and anxiety, culminating in planning a suicide last March. I told her that I had called a help line, gotten treatment first from a general psych, then was referred to a specialist. The specialist worked with me and after a few months sent me to see an endocrinologist, who ordered tests and an MRI, confirming a problem that was treatable.
Then I described my prenatal DES exposure, and how it had likely 'flipped' certain genes off and on in my development somewhere around the 12th week of pregnancy. My mom had told me about my exposure about 10 years ago, and I connected the dots this summer. I showed her my finger digit lengths, and compared them with hers and later my son's. (The 2nd and fourth digit lengths are identical on my hands, a female marker, rather than obviously different lengths on my son's hand.) I described my childhood in general terms, that I didn't start puberty until I had testosterone injections, the effects on me, and how the local priest convinced me I was 'cured' as long as I avoided impure thoughts.
I talked about how, being 'cured', I went off to college, met my spouse, got married, and eventually after infertility treatment managed to conceive my son and daughters. I went over what I called the 'noise' in my head, how it got worse over the years, eventually driving me to suicidal depression. I described how radically this was improved with HRT, and went over what it was doing to me. I told her about the physical changes from HRT that were happening, and how I found that I liked it, but I needed to tell them what was going on before the changes became too obvious. I told her that the medical results showed that I was technically an intersex person resulting from chemical exposure, which meant I am a sort of transgender person. Because I have sought medical intervention to alter myself in some way, via HRT in my case, I am technically a transsexual person. I am still attracted to women. "Daddy isn't gay. Daddy is a lesbian."
My daughter immediately wanted to know what my pronouns were! OK, she's had some experience with us folks before in her job. She was incredibly open and accepting, which had me crying. (It still had me crying. I'm getting the keyboard wet.)
And that's when my spouse walked in on us. She was furious, and took me aside. "You know I didn't want you saying anything about THIS!" "I'm sorry that you are so upset, but I had to tell them. I can't keep repressing and hiding this, and they deserve to know before they start wondering what is happening to Daddy." Oh, this repeated over and over, different variations on the same theme. Apparently she wanted me to keep this secret until I got better, or was over this phase, because it makes her uncomfortable. I said that would make a fine epitaph. "At least he didn't make me uncomfortable."
She than forbade me from telling her relatives, her sister, brother, or mother. (A little too late. Her sister knows I'm getting medical treatment for some sort of neuro-endocrine issue. As in "Why do you have Estrodiol patches in your medicine cabinet?" The prescription packages are made out in my name, not my spouses...

)
My son wanted to know what the fuss was about and why my spouse was so upset. She told him to ask me, so I went through this all with him. Since he is Christian, although NOT an evangelical or fundamentalist, I finished up with the ethical delimma as to whether I should hide or go forward, couched in terms of the Parable of the Talents. I've gone through that in the Christianity area before and won't repeat it here.
We continued conversing about this a little while, than I fixed dinner and my som and I chatted about other things. We finished the evening streaming old "Office' episodes with my spouse and I on opposite ends of the couch, son in the middle, and the two of us laughing together while my spouse sulked and poked at her phone on her end.
Tomorrow we have a big event with the extended family. I'm sure my spouse thinks it's ruined already, and is cursing my existance.
So, I may be living on my own and going full time fairly soon...
So it goes. So it goes.