How come telling someone they don't have a life is so offensive now a days?

When in doubt put yourself on the receiving end of that statement! When you tell someone they don't have a life then you have stripped them of their identity. Everyone has character flaws, but it gives you no right to be judge and jury of this person. If this person is having some problems in their life then unless you don't want to help them then say nothing! If you do want to help them then do it out of kindness and from the heart and for all you know they could be depressed, be abused or a myriad of other problems. YOU don't know everything about each individual person and, in fact, you don't even know yourself 100%! That goes for each individual. 'Get a life' is a cliche in today's culture and means 'get off my back and go away' to other meanings. Don't get this confused with telling someone they don't have a life! 'Dogs are smarter than humans .... they wag their tails, while humans wag their tongues' (sometimes too much!)