knots around responsbility

my head is a bit more muddled now than when i first started thinking about responsibility.
In some ways I'm clear and i know it's both simple and complicated.
We are all responsible for one another, that's what community and society is - if we only look out for ourselves it won't work, our well being is inextricably tied up with everyone else, if there's any one of us who is not happy then none of us can be truly happy.
And I also know that some of us can take on too much responsibilty, carry the world on our shoulders, think that everything is down to us and feel responsible when actually we're not. In some ways, we're only responsible for the way we react to how we feel. I'm not responsible for how others feel, but does that mean I'm not responsible for how my actions leave others feeling.
This is where I get less clear. Let's imagine someone says something that I feel is mean - this might be deliberate or unaware. I now feel upset - is this their fault? Do I now hold them responsible or do I own the feelings as my own, triggered by someone/something external? Is it down to me to notice and then react to my feelings in the way that makes most sense to me or can I legitimately say it is them that "makes" me miserable?
I then - possibly unhelpfully - tried to use a metaphor of a car accident. Say I was arrested for driving irresponsibly that caused someone else to be physically injured. In the court I would be found guilty for causing harm - the responsibility was with me to drive with care and attention and my failure to do so hurt someone. I suspect it not only would hurt them physically but emotionally too, so has my thoughtlessness created feelings that are legitimately blamed on me?

I think I need to keep working on this. Let's eat and try again tomorrow :)