So, forget about blaming the EU for your sad results.
Clearly you didn't read what I wrote.
In my final paragraph, I pointed out the UK Brexit team didn't handle the negotiations well enough, so I made it clear that was their failing. That doesn't invalidate the Leave vote itself though, nor does it mean the EU were blameless throughout.
Besides, there are are no "sad results" - ultimately, the UK has left the EU's political structure and will not be sucked into closer political or monetary union, which was primarily what the Leave vote was for. The future outside the EU is still being shaped, we haven't reached the "result". It took 40+ years of being drawn deeper into the "project" before the UK vote in 2016, so it will take some time to fully extricate the country and set a fresh course - something that Remoaners overlook in their rush to cry that the sky is falling in without EU membership.
In the meantime, diplomacy works both ways. Just as there was no "obligation" for the EU to be "kind", nor is there any longer any obligation for the UK to show sympathy or support to the EU in its difficulties. However, I would hope the UK would not be as petty in response as the kind of attitude you ascribe to the EU.
Interestingly, the frosty relations between the UK and EU are already thawing, partly because of the challenges brought about by the Russia/Ukraine conflict. That's caused much more difficulty for the EU due to the reliance of many of their members on Russian energy, and the internal political and diplomatic differences over how to respond. I suspect over time, as the EU and UK settle into a new, more separated relationship, things will begin to smooth out as other mutual priorities like international security and refugee migration become more urgent.