The advice above is great but I can still imagine you aren't sure whether to give the letter or not.
I may be an idiot - and chances are, I am, given what I've brought down on myself - but I'd be tempted to ask her.
That is, say something like "A couple of days ago you mentioned that you'd like to hear what I said to my parents about... If you're interested, I've written something down/jotted down a few points."
And then you can hand it over if she says Yes.
If she says No, or gets angry, then I'd back off for a while.
But at least you'd have planted a seed that might take root at a later time. And she'd know that you'd been reflecting and working on yourself in a serious way, even if she wasn't prepared to read the full details.
