... and it's making me very angry. If he'd just acknowledge he might have done something that's gone wrong and say 'sorry about that' then I'd probably just brush it off and say 'no worries' but as it is, we end up having huge arguments and then he sulks.
So today's example:
We have a length of fence which has a lovely, old, clematis bush running along it (about 6 metres or more). Part of it has an empty border in front of it which we didn't get around to planting bedding plants in this year due to lockdown etc. Weeds were starting to grow in it, so last weekend DH suddenly decided to spray them all with weedkiller (he seems to have an obsession with jet-washing and spraying things 
)
Today I noticed that all the leaves on the Clematis behind the border area have shrivelled up and died (just like the weeds in front of them!) so I said to DH (non-confrontationally) "I think you've killed part of the Clematis, as well as the weeds".
He just completely denied that it could possibly have ANYTHING to do with him and the weedkiller and was trying to argue that it was my fault for cutting back the Clematis too hard at the beginning of the year (despite the fact that the rest of the bush is absolutely fine?).
It is so VERY obvious that the weedkiller spray has been blown onto the bush behind it!
Why does he do this? What does he think it achieves by trying to deny, lie and bluster his way out of it?
(This is just one example - there are many, many more...) 