do something to make a bad situation even worseContext:
-Hi Lilly, how was your week?
-Hello Jane, life hasn't been the best the last few days, if I'm to be perfectly honest. Ben has been really adding fuel to the fire recently.
-Oh, yes? What's going on?
-Well, he's thinking about moving to Australia to work but I like Switzerland... and we've been quarreling a lot because of it. I guess that wasn't enough though because now he's saying he wants to adopt a cat! Yet he knows I hate cats!
-Oh, dear me! That does sound like quite an argument!
Notes: This is a metaphorical idiom.
The fact is that by adding a fuel, like petrol or wood, to a fire will make it burn brighter and hotter.
This is a metaphorical idiom.