This is a good discussion. It can be for spouses, but also for religious orders and even particular convents or monasteries.
How much of it is our choice, and how much God's will?
Obviously the decisions we make are our choice. But what happens is always God's Will. (incidentally, Vox Day is a Protestant heretic who doesn't believe in God's foreknowledge).
I suppose the principle to keep in mind, that can seem fatalistic sometimes, is that God will not let us have anything he doesn't allow us to have. And if he doesn't want us to have something, and we try to take it, there's a good chance we'll be separated from it.
That being said, there's no doubt God gives us opportunities and it is our responsibility to act on them. Recall the parable of the talents.