As a 6 year survivor of dropping the T-Bomb, a lifetime observer of people, and person that gets paid well to what-if things to death I'll add in just a bit more to Cindy's list.
We keep this deep dark secret totally bottled up for most to all of our life. Eventually the point comes we are about to explode over it, or, our life exploded once again because of it. We take that first most terrifying step of actually saying the words to another person, a person you love, a person you trust, a person you want to continue sharing the rest of your life with, that you are trans. The first 30 milli-seconds afterwards last an eternity as you wait.... No lightning bolt? The Earth didn't swallow me up? No micro-meteorite crushing my cranium? Wow! That went easier then I thought.
Three days later it's 'Damn the torpedoes and full speed ahead'.
Full speed being a relative term, relative to how well, or not well your SO is taking the shock. Absolute to reality since many aspects of transition just plain take time to get the best long term outcome (unless the alternative outcome is waking up on the wrong side of the dirt). Taking precious money away from other family resources is yet another whole level or two or three of escalation. You have a partnership. You have needs, she has needs the 'Us' has needs. Needs being emotional, financial, spiritual, familial, whatever else. All competing with each other. All need to be managed somehow by consensus or dissolve the partnership.
We spent a lifetime just barely getting a good enough handle on this to take this step. Your SO has had only minutes, hours, days to get over the shock, much less all the other raging reptilian emotions. They likely have a thousands questions, overwhelmed not even knowing where or how to even start asking them. We barely have answers to some, and even those are far from etched in stone at this point. Don't take passivity for acceptance. Assume "At least I am not getting strangled... yet".
It took a good 5 years before my wife came to really really trust me again. Yes, things were shakey even before me dropping the T-Bomb. Over time she has been seeing my own personal growth. Seeing me become a for real person. Seeing me grow towards the person she always saw I was capable of. We both put in the hard work to keep the relationship going.
I never asked, nor is it fair for me to, if she will stay with me if I go full-time. I can't expect her to, only hope so. Six years ago transitioning was the last thing on my mind. Been there, tried it twice, and I was still opting to find some sort of "Normal". As she often reminded me of early on, "I did not marry a woman. If I knew then that...." Today the final outcome of a full-time transition is even hazier then ever. So is the question of going full-time for me.