It can be exhausting but you must endure. I have been taking a different approach recently. Rather than giving them the whole Bitcoin 101 or defending mining's energy use, I just say something like "Most people have strong opinions about bitcoin but regardless of your opinion, we keep seeing examples as to why the ability to be your own bank, store and port your wealth across the world without counterparty risk is such an incredible innovation". Most won't have a clue what you are talking about but the lightbulb might go off for some and then they will ask you questions.