Look back three years and you’ll find you’re braver than you used to be. Time plus trying does that.

Courage grows quietly enough to be easy to miss. Things that genuinely frightened you at thirteen are unremarkable now, not because you decided to be brave but because you did them a few times and the fear wore down. Progress like that is invisible from inside, since each new level of normal arrives without any announcement.

Think of something you used to dread and can now do without much thought. That is evidence about how the process works on you specifically. Apply it to one thing that scares you now, in a small first version, and expect the same slow erosion.