They are not things to do. They are not things to worry about. They don't come into our heads as projects to work on. They don't come into our heads as items to tick/check off. They don't even come into our heads as things to even think about!
It is us that decide whether those thoughts and feelings become those other things.
There is something in our brain that decides. There is some sort of decision-making machine part of our brain that is constantly observing these thoughts and feelings, like a claw above a conveyor belt. These thoughts and feelings come across on the conveyor belt and then when we think, "Oh we need to action this thought," then the claw picks it up and puts it somewhere in our brain to work on. Or if it sees the feeling and decides, "Oh this feeling needs to be felt a bit more," and the claw picks it up.
We decide how busy this claw becomes. When we decide think too much or when we decide to feel too much, this claw works all the time, constantly picking up thoughts, constantly picking up emotions and feelings, and putting it into our to-do list or to-feel list. When we're just observing these thoughts and feelings go by, the claw doesn't move or hardly moves.
The question is, what makes the claw move? What makes the claw work? I guess it's emotions, strong urges, trauma, promises we've made to ourselves, and promises we've made to other people. All of these things live inside this one decision-making machine in our head.
The more in control we are of this decision-making machine, I think the calmer we become.
And the better our mental health becomes.