Have you ever thought about all the components of your day and just sat with them for a few minutes?
I tend to be very in the moment, and if this present experience is negative, then it's pretty hard to feel good about my life. However, if I review the day, generally, there are some good things that have happened somewhere along the way.
That's where I want to place my focus.
Perhaps as you go through your day, you can "mark" a place that you want to remember as being positive. Then when the irritations and hard places come (and you know they will) you can say, "Yes, but remember – that's not all this day has been."