Social Networking does privacy mean anything there?

I have been on Facebook for the past 2-3 years. It has been a platform for me to voice out my feelings in real-time. Sharing thought, pictures and links was all it was about then. Some people have met though Facebook or have been reunited with long lost friends. My friendship list has topped the 750 mark. Which i guess most will say i am an addict. As Technology evolved so did all these social networking sites conform to keep up. The internet is big now the life source to many businesses, Organizations, Individuals etc. Only one problem always prevails does privacy exist on the internet. I am not referring to fraudulent schemes (Phishing, spamming etc). I am referring to our status updates, picture sharing and blogging, Can you really say whatever you want to say without being scrutinized. Through my experience with my 750 friends and 200 followers. I have realised that it's not possible. My girlfriend of two years has not yet been bitten by the Social network bug. For the past few months i was using these Social networking sites for seeking advice about our relationship. Only to find that all my status updates, comments, Likes and dislikes were being flooded to my girlfriend, which led to World War 3. We survived the war fortunately but that has made me realise that Privacy does not exist in these realms. In the news a few days ago a certain lady was being prosecuted for posting pictures of herself while she was in there army. This proves that freedom is not as free as we perceive it be aware of what u say, post or share. Social networking sites are for us to be socially active, discuss Social events, places and people do not i repeat DO NOT mistaken it for your Journal or diary.