I think the best way to shut up bitcoin haters is to prove that you are earning on bitcoin. When I was starting at bitcoin, there are a lot of negative comments from my friends and they were always telling me to be cautious. Only a few of them supported me and those people are investing on bitcoin as well. They are earning enough money for their needs and they never regret investing on bitcoin even if the price goes up and down.
We share the same thought. If you really wanna shut up the bitcoin haters attack them by proving that bitcon is real and you can earn in here. Let them see the evidences of your success in bitcoin because fighting with them by talking is nonsense. Not minding them is also a way to shut them up. Let them bark and bark at you and bitcoin because they don't have any information on how great the bitcoin is. Always remember separate your self from nega people. Be with someone who will support you.