For example I could have a great successful day and then the next day can be just a total points failure why can't this be controlled ?
Our perception of reality is based on our foundation premises. These premises structures how we perceive reality. A Democrat or Republican can see the same data, but each can draw different conclusions. It is like processing cream to make vanilla or chocolate ice cream. It depends on how you dial it in with the foundation premises.
in terms of personal life and emotions, if you are irritable, the sound of the birds can get on your nerves, The next day, if you feel in love, the same birds making the same sound, is now beautiful music. Reality has not changed, but rather what has changed are different foundation premises, in your own brain, each processing reality in different ways. This is less intellectual, but more mood dependent.
This has to do with our memory, and how the brain writes and stores memory. Our memory has both sensory content and an emotional tag. When the brain writes to memory it adds emotional tags to sensory content. The emotional tagging cause the memory to be stored in layers, with all things with the same tag, on the same layer. In the example, in the first paragraph, the same birds are treated differently in each layer, since each layer has a base emotional lag; love or grouchy. Each layer can form its own set of foundation premises, based on the summation of data, in light of the attached emotional tag.
This layering is useful to the animal brain, since each instinctive feeling will induce a specific layer. This helps to narrow down memory and motivation to what is needed for that instinctive feeling. If hungry, then just images of food and food retrieval all appear with their minds and their perception will focus to the needs of hunger.
In the case of humans, we are more complex, we could have a love layer, that once active, see reality through rose colored glasses and then stamps new memories with the same feeling of love. But if we change to a different layer, often by a trigger, now the world feels grouchy and if this impacts perception, it too add this tag, to new memory, to reinforce the grouchy layer. Depression is a layer and if you get stuck there, it is self feeding and hard to break away from. It keeps on stamping until depresses is all you can see.
The trick is to think of the layer you want, by remembering that feeling and one of prime memories, until that layer reappears. Older people may think in terms of glory days to recreate that time of being at the op of their game. The brain seeks completeness and may cycle through all the various layers periodically, but you have some control of what you think and feel and which layer.
This is all done with brain chemicals. At times, the brain will want to manufacture one kind of chemical or chemical combination, to turn on a given layer. Even if you try to change that layer, it can take time, before the previous layer's chemicals are flushed out the of cerebral spinal fluid. So be patient. I like to go for a walk, to circulate my blood, with walking often bringing me to a natural layer, as a placeholder, until the body absorbs the previous chemicals. But for the most part, I can keep the pleasant chemicals on.
As an application, what I noticed is the Democrats tend to form foundation premises in the fear and anger layer; hate trump. That is not the best layer if the goal is objectivity. But the leaders knew it is the best place to groom 1-D minions, where reason is not fully available. The good lawyer is within the clan. The love layer is the best, since love integrates, and gives a more 3-D view of reality; all accepting.