Again: the focus is, "What if it doesn't work out and she takes all of our future stuff? I need protection from whoever she is going to become then ... I need protection FROM the very one I am promising to protect with my very life, until death." You don't have any of the stuff. You don't know what the future holds, but ALREADY ... you have a whole script written out for it based on fear.
"The heart of others is land no one treads" -- GENERALLY, this is true, but if we are speaking of marital love, you are getting to know and explore someone else's heart, and plan to love it to the best of your ability. Not others. JUST ONE, the one you say you love. Again: if you are defeated before you even come in -- if you are convinced you have no agency in building LOVE with that other person -- not things, which is all you mentioned -- then of course, fear and defeat run together. As a woman, the most dangerous thing I could EVER do is live with a man who already feels I am unknowable, treacherous, and with the capacity to completely defeat and take from him in the long run, with NO SENSE that loving me well over time will make a difference, and NO CAPACITY BUILDING for loving me well. I simply would never do that to myself, no matter how much I loved that man ... I cannot live in a future in which he has already decided I'm his worst enemy.