So you don't believe that the OP was ill, even though she said she was, but you do believe the OP may be a drama queen, even though there's no evidence of that? The facts are: she asked her DP to come home early, he didn't come home early, instead he fucked off to Tesco to buy chocolate. Ok, not a crime, but clearly not very considerate. Instead of apologising for being a bit thoughtless, he told the OP she was "ungrateful." So, overall, he was shit. If the train had broken down or there was traffic he wouldn't have been able to do anything about that and being upset out it would have been pointless. He chose to go to Tesco, thus totally disregarding what the OP had asked for. Again, essentially a bit thoughtless but not the crime of century. In the case where you've been a bit silly you apologise. Far from apologising the DP got cross and stroppy, ie he was a shithead about it. Expecting basic courtesy from a partner such as expecting them home when they say they'll be home because you're ill and need help is not too much to ask.
^^This
I will never understand, why there is the frequent opinion on MN that we should be grateful for any gift from spouse/partner, however useless, unwanted or inappropriate, because at least they were 'thoughtful'.
Not in my book they're not. They're just looking (in the wrong place) for brownie points. They haven't listened to what you actually want or need. The OP needed her husband at home. Not buying chocolates she couldn't eat.
Also, however bad your situation, there is always someone, somewhere, who has it worse. Either a little bit or life-alteringly completely worse.
Doesn't mean you're not allowed to be pissed off or upset with what you are going through.
And an online forum is an appropriate place to speak your mind about it.