Friend,
Once in a while, my mind runs off track like a run-away locomotive, onto the track of worry and overthinking. It starts to swirl with thoughts of worse case scenarios; thoughts like "am I going to get sick and die", or "I am ever going to be able to earn a living again in my profession" to "will we ever be able to go back to a normal life". Can you relate Friend?
Your thoughts really are like a run-away train, they pick up momentum on the track you leave them on. Now, more than ever before, mindfulness is critical to well living.
Since no 2 thoughts can co-exist in your mind at ONE time, you MUST choose the thought you allow in. When you practice mindfulness, you bring your mind's attention back to the NOW instead of obsessing about past scenarios that you cannot do anything about, or conjuring up future dooms-day scenarios that 99.9% of the time will never come to pass.
Mindfulness is the act of focusing all your attention on a task/experience/thing - where all your senses are engaged. It's like experiencing something for the 1st time, so fully and so vividly.
Not only does it help re-train your brain from past/future living, it also calms your mind and, as a beautiful by-product, increases gratefulness (and we all know that gratitude is one the best emotions to feel as it raises your body's natural vibration that, in turn, improves your whole being).
Let's look at this side-by-side comparison.. | 
