Yes it is dispiriting I imagine, but if it keeps happening over very similar sorts of issues, then surely the answer is staring you in the face?
If your DH has never mentioned that he doesn't like strawberry and only eats lemon, then you'd be right to feel dispirited. You aren't a mind reader. But if it's been mentioned on numerous occasions and you still keep 'forgetting' and buying him strawberry then I can see why he'd be a irritated by it. It's not anger so much as just bewilderment and frustration. You feel like 'does anyone ever actually listen to anything I say at all?'
Things like this get pretty dispiriting for the person on the other end as well. Sometimes exasperation gets the better of us. It's a mystery why some things that should involve very straightforward and non-complicated problem solving can be made such an utter hash of by someone who seems incapable of applying any common sense to the task.
A classic example is people who keep overstuffing the bin bag until it's impossible to remove it from the bin without it splitting and the contents going all over the floor. No matter how many times it happens, clearly they feel that removing the bag before it's over-compacted is harder work than clearing up four day old raw chicken juice and baked beans from the floor.
People who can't seem to grasp the basic rules of recycling. You can't just chuck it all in if it's still contaminated with food. Make a judgement call. Where cardboard and paper is concerned, if it's clean and dry, recycle it. If it's greasy and contaminated, don't. Where plastic is concerned, if it's fairly simple to rinse or wash it first, then DO. If you think it takes more hot water and scrubbing effort than it warrants, then don't. But don't act like a moron and pretend not to understand the difference. It's not like it hasn't been explained to you enough times.
People who open packets of ham, bread or biscuits and then chuck them in the fridge or cupboard without bothering to re-seal the packet then they wonder why they are all stale/soggy or shrivelled/dry two days later and complain that there's nothing to eat.
People who hang their wet towel over the top of someone else's dry towel. News flash matey, your wet towel will NOT get dry like that. All that will happen is that you will make the dry towel damp. And yet when this is pointed out for the tenth time they act like they deserve a medal for hanging the towel up at all and you are just ungrateful that they performed this arduous task.
Stupid things like opening new jars/bottles/packets of things without checking in the fridge/cupboard to see if there is already one open first, so we have two lots of something open which takes ages to use up at the best of times.
Having two cartons of milk open, then deciding the pour the remains of the milk which expires today into the carton of milk which still has six days on it, because you think you are saving space and being efficient, when actually you are being a numbskull.
Cleaning up after dinner by filling casserole dishes and roasting pans with water 'to soak' but not bothering to scrape the remains out first. So the following day you have 3 pints of cold, lumpy, greasy slurry that's too chunky to pour down the sink and too watery to put in the bin and is so revolting that no-one knows what to do with it for the best. And you wonder why the kitchen sink keeps getting blocked.
Not listening when told that very thin wine glasses will break if you keep loading them into the dishwasher in that certain way you keep doing. Then wondering why we only have three left from a set of eight.
Continuing to ball your dirty socks up into pairs because 'it helps keep them together so they don't get mixed up' even though I keep telling you that they need to be unballed to put them through the washing machine anyway.
If we shout and get snappy occasionally it's because we are fucking exhausted with it all. Honestly, we tried asking nicely the first ten times. It went in one ear and out the other. People only seem to notice what you say once you get mad, and act all wounded like it's the very first time they've heard it.