Happiness doesn't come from what happens to you, it comes from the viewpoint you look out from. One of the most important steps I took in becoming pretty darn happy most of the darned time was changing how I view other people's actions.
Example one - A person pushes in front of you, without even acknowledging it. They may even huff or sigh as they do so, as if you've got in their way.
It's very easy to fall into a mindset of exclaiming how rude everyone is these days, that no one has any manners, and walk away from the experience feeling bitter, cross and frustrated. However, it is possible to flip this on its head. If you try and see the good in the world, you'll see more good. So perhaps the person who pushed you has just received bad news, or is in a rush as someone is ill at home, or just lost their job, or is dealing with a messy divorce. The world can be a tough place, and not everything is about us.
Example two - You're meeting someone, and they're late. They may have messaged you, with some lame excuse, or perhaps not even at all. You're waiting, maybe even in the rain, getting more wound up as each minute passes.
How dare they not value your time? Weren't they raised with manners? Maybe they don't even like you very much, it's not that hard to work out how long it takes to get somewhere. They're always late, as if they think they're more important than you.
I've worked out that one of the biggest reasons for people's lateness (when the same person is always late) is actually their optimism. They truly believe that it will only take them 10 minutes to get ready (when it takes 25) and they really think the bus journey is only about 7 minutes (when its nearer 15). Time runs away from them as they're just terrible at estimating their own reality. Often lateness has nothing to do with you, but them. They may be scattered at home, and often are unable to find their keys before heading out. They may be a classic people pleaser, simply unable to say no to the other demands on their time that day.
Example three - People not offering a seat to a pregnant lady or an elderly person.
You watch a vulnerable person get onto the bus or train, and watch them struggle to hold on, while no one offers their seat.
It can feel like no one cares about anyone else anymore, that we're living in a world with no respect or values. We've stopped looking out for those more needy than ourselves.
With our technology-led lives we actually just often don't see those people around us, or we may just be buried in a book. Chances are that people haven't noticed someone needing a seat, and would happily give up theirs if they were prompted to (politely). It is also very possible that a person not offering a seat has their own silent reason for staying seated. Many illnesses and conditions are not on public display for us to be aware of.
It's irrelevant whether the positive explanations are actually true or not, what matters is how you experience your day. Seeing the kindness and good in people makes for a much more pleasant ride than always thinking the worst in people.