The discipline of thanks only comes with practice.
When we practice giving thanks, we practice the presence of God, stay present to His presence, and it is always the eyes, and a practice of the eyes.
We don't have to change what we see, only the way we see.
Why is it so hard to re-tune the impaired senses to sense the spirit I wonder? To see the grace before us in every circumstance? Why is it so hard? Practice. Practice. Practice.