I don't have the energy to be angry with 'rule-breakers' and has been said many times on here, people will suit themselves. Family circumstances sometimes have to take precedence. Common sense can be more important than a rule book. I don't think it's that people do not understand, but more likely people interpret things to fit them, their lifestyle, their current needs. There will always be exceptions to the rule, emergencies that do require a decision on the spot. And there will always be that selfish minority that don't give a damn.
My better half is grieving for one of his oldest friends who had a potentially-life-saving operation cancelled - there were no guarantees, but without the op his fate was sealed and he died a few weeks ago. He wishes he'd gone to see his friend, feels guilty, has regrets - but he didn't want to put his friend at risk, or me, or himself, so knows he did the right thing even though it feels horrible.
Another point I would make, back along the common sense line, is that just because something is a 'rule' or you are 'exempt' doesn't mean a licence to do as you please...My health issues would render me exempt from wearing a mask and admittedly I rarely leave the house anyway, but my better half supplied me with a few in case I need to open the door, take in parcels etc. The one time I went into a shop I chose to wear a mask - for my own protection and that of others...I figured if I started to have breathing difficulties I had my inhalers handy and am capable of asking him to help me leave the shop. I have severe breathing problems yet I coped with the mask - it was a little harder to breathe but not impossible...my point being if I coped others could too!
I fear this virus will be with us for a long time yet as human nature gives it plenty of scope to spread and continue infecting more people. Certain events change the world and the way we live - world wars, days like 9/11 and now pandemics...I think we will have to get used to a new way of living and each be responsible for protecting ourselves, our loved ones, and the wider population.