Annie, both of my marriages ended long before I began transition, though the second one did end when I came out as gay, but anyhoo, I can't relate to your situation except to feel for you as a sister.
This is the thing about transition, at some point, ...shits gonna get real. Just do yourself a favor and make damn sure you're ready for it.
F all of us tranny broads on this forum, do what's right for you. Nobody here has any stake in your life, and if your wife leaves you, then what?