Good luck on talking tonight, I hope she responds to your note.
Gary, I'm going to push on you a little bit the same way I have pushed on others in this forum....you say that "she won't talk". But are you sure this is the case, or have you just allowed her to shut you down on the topic? Why is SHE the only one in your marriage of two partners that gets to decide what will be talked about and what will not? My guess is that you are afraid to approach certain subjects, and she finds it easy to just shut you down by saying "I don't talk about that stuff, it should just come naturally". She says this with conviction, so you believe her and back off. What if, instead, YOU said with conviction "Wife, we need to talk. And I will not accept you just blowing me off on this, we both really do need to talk. If you have nothing to say on the subject, then you can just listen to me talk".
And if she really does just listen but won't talk, then be prepared to just tell her "like it is". Meaning, dump all your feelings and thoughts on the subject upon her table, if she is in listening mode.
You might be surprised that simply by standing up to her and talking anyway, whether she does or not, will prompt her to talk.
Let us know how it turns out.
As for the addiction issues, I wouldn't mention sex addiction to her, as from personal knowledge I understand that this is a tough thing to really "get" about yourself, especially if you aren't actually having sex. Its hard to understand that sex addiction sometimes does not involve sex itself. So for now, if I were you, I would focus on her alcohol addiction, if you are going to bring anything up regarding addictions.