A steadier ground guide to deciding who gets to know, and how much. What the hesitation is actually protecting, how to tell people without losing your own footing, and when staying quiet has started to cost more than telling would.
Notice the flinch before you decide who to tell next. It isn't only privacy you are protecting, it is your own footing while you are still finding it, and that is worth naming before you pick up the phone.
Before deciding who to tell, ask whether the hesitation is new, or whether privacy about hard things has always been her way, and yours. Some families have never discussed illness or difficulty openly, and this reticence is one more instance of that pattern rather than something the diagnosis created. It's also worth checking, directly if you can, whether she has an actual preference here. In early stage she often still does, and some people want their closest circle told right away because pretending costs more than the diagnosis does, while others want as few people as possible to know for as long as they can manage it. Neither instinct is wrong, and finding out which is hers changes what comes next more than any strategy you could build without her.
What's actually underneath the hesitation is rarely the facts themselves. It's what happens to you once someone else has them. The moment you tell someone, you stop being able to manage the impression they form of her, sometimes kind, sometimes closer to pity than either of you wants, and either way it becomes theirs, not yours to edit anymore. There's also a quieter fear worth naming: that once it's out, it becomes real in a way it hasn't fully been yet, even to you. Waiting can feel like holding a door shut on something that hasn't finished happening. That instinct is protective, not dishonest, even when it starts to cost you.
The distinction that matters here isn't whether you've told enough people yet by some external measure. It's whether the silence itself has started to create a cost that falls on someone besides you: isolation that's cutting you off from help you need, confusion in people close to her that's curdling into judgment because nobody explained it, or a safety-relevant blind spot, a coworker who doesn't know why she seems off, a driving concern nobody outside the house can weigh in on. A slow, ongoing process of telling people in your own order and your own time is not a problem to fix. A specific silence that's actively costing someone something is worth naming and addressing directly, even if the rest of the disclosure stays unfinished.
If you're stuck between saying nothing and saying everything, there's real room between those two.
Note who you've told, what you told them, and how it landed, relief, distance, over-involvement. Do this for the people closest to you first. A pattern will usually show you whose reactions you can lean on and whose you need to manage more carefully before you widen the circle.
Print the one-page log if you want somewhere to keep this, and take it to the appointment.
This is what the tracking is for. Which reactions you can lean on and which you can't turns "I don't know who to tell" into something you can actually plan around.
Telling people doesn't make this more true than it already is. It only means you stop carrying the truth by yourself.