Unfortunately you cannot decide if other people think you are rude. That is their decision. I am pretty much in the same boat as you and a lot of what I say is tongue in cheek and not meant to be rude or offend anyone.
This works well with face to face discussions with people I know as the intent is clear. It doesn't work so well on internet forums and even though I know that, it is hard for me to change how I interact but at least I realise it and am prepared to apologise if anyone takes something the wrong way. If someone feels you have been rude then saying 'you need to get out more' to them is not an acceptance of how they feel and just adds to the rudeness (the rudeness that you don't even realise you are doing)
And smilies, emoticons, other methods of implying things have been on internet forums since internet forums began. Before that people actually spoke to each other in real forums, 1-1 etc,. so it wasn't necessary.