I think that most of us could take lessons in learning what to walk by and ignore and what to truly take issue with. I know I could. I sometimes take issue with things that twenty or thirty minutes later seem incredibly trivial, and definitely not worth the time and energy I had spent stressing out about it. I might take issue with the fact that a neighbor is being loud, only to realize in a while that they really aren't being all that loud--just a bit louder than normal, or a bit louder than I'm used to. I might take issue with a person's comments about someone or something, only to figure out later that that person had every right in the world to make the comments--or that the comments themselves really weren't what they seemed to be.
Sometimes, of course, people do things that we must take issue with--things that harm other people, or have the potential to harm others. But most of the time I find that the things I take issue with really aren't issues at all, and I'd be conserving my energy and feeling much better in general if I just let them slide right by me, focusing instead on getting the most out of all the positive things that I do have in my life.