If you drop this kind of bomb on your spouse then you're an utterly selfish and despicable piece of shit.

Traditionally, when two people get married, the assumption is that by that point, each partner has declared all of their negative peculiarities and both agreed, in spite of those negative traits, to accept the other person in their lives 'until death'. You trust that, for the most part, the person you're with won't change too much, because having that stability is essential.

So to introduce egregious life-altering surprise bullshit about yourself in the middle of the marriage is a real piece of shit move. At the very least, you've betrayed your spouse's trust. But more likely you've shattered their reality and wasted years or decades of their life.

In this case, I don't care if the desire to be a tranny just came out of the blue. Tough shit, you're married with kids, you don't get to be a tranny. The window for that is long gone. Suck it up and focus on being a good husband, not a tranny.