Hi Rod, I've had a troll or two in the past on other formats. The way to deal with them is to ignore and as you say, use it as fuel. It's always tempting to fight back but I always tell myself that they do it because they are hurting.
They have some pain in their life and this is their way of letting out that anger. I feel sorry for them more than anything. No one who is truly happy has time or the will to go around comments sections being nasty. Never retaliate, it's what they want because it then gives them validation and an excuse to do it even more.
Very true mate. Best way to kill negative energy is to starve it :)