I don’t know your friend, nor her theology, and I wouldn’t wish to guess what she means in saying that your misadventure was “all in God’s plan”.
Perhaps she’s a Calvinist, in which case you may be right that she’s envisioning God as a “puppet master”. On the other hand, one doesn’t have to look at things in so predestinarian a way to use such an expression. To suppose—as I certainly do—that there’s some deep meaning, or inner significance, to the events of our lives could be “translated” into more or less anthropomorphic terms by saying that Heaven “has a plan”.
Considering our lives in this way is no threat to free will, as you seem to think. True enough, if freedom consisted merely in fork-in-the-road choices between horizontal or planimetric possibilities, there would be a problem. Jonathan Edwards was surely right: confronted by the world, we always choose the greater apparent good, and not being responsible (or not directly so) for the mechanism that generates the appearance, we’re not responsible for the choice, and thus we’re not really free.
Genuine freedom, however, is vertical: it’s our ability, though rarely exercised, to take a step or two back from what’s going on, whether outside our bodies or inside our minds—to detach ourselves, even if only for a split second, from our ego’s reactions, worries, frustrations, desires; its likes and dislikes, its ups and its downs—to watch ourselves, as if from above and from the point of view of a larger perspective.
That larger perspective, speaking very elliptically for the moment, is “God” … or at least a dimension of Him.