No one attacked your intentions. If you are that sensitive, an internet forum is not going to be an enjoyable place for you. Questioning and attacking are two different things.
Just as you questioned this nurse, we are questioning you. If you don't like it, then you don't have to read it. Or better yet, don't let it get to you. Why get offended at what complete strangers say?:smackingf
Just so you know, an internet forum is where you will probably find the most honesty, so you have to be prepared for it.
Personally, I think your reaction was immature and unprofessional, but you admit to that, and I can respect that. There are people at work I don't like. But no matter how much I dislike them, I would ALWAYS go to them first when something serious arises. I don't believe in going over someone's head. It could have been as simple as sending a FB message (not a wall post) letting her know that her post may be a a HIPAA violation and that you just wanted to let her know so she wouldn't get in trouble. THAT is professional and called common courtesy. Now, if she blew you off after you warned her, then I can understand going up to her superior. That is IF you are 100% certain it is a HIPAA violation, otherwise, you will make yourself look like a fool to your boss and I'm sure you wouldn't want that.
While I respect the fact that you want to make sure rules are followed, how would YOU feel if you were in her shoes? If you were hurt emotionally over the loss of this patient and you made an honest mistake but someone went ABOVE your head and reported you? Wouldn't feel too good would it? We don't always think when we are upset.... and that goes for you and for this nurse in question.
If you are upset about something, always take time to think before you act. What if you DID make her lose her job, and in this economy, she may have had a hard time finding a new one. I don't know about you, but I would feel even crappier if I knew my actions caused someone who made an honest mistake to lose their job.
Now, part of me wanted to rip you a new one, but you admitted that what you did was childish, so I respect you. That is very professional and mature of you. Many people have a hard time admitting things like that, so I always find it respectable of a person who does. Despite the mistakes you may have made, you came back to realize you were also in the wrong, that is the sign of a true professional.
I hope you can learn to enjoy this forum. Always expect honesty, it can hurt, but you gotta just let it roll. It can be amusing too. :)