It is amazing how our thoughts can own us. They can take over our affective states and disable our ability to function at a high level or even normally. Incessant thoughts bombard us at tremendous speed with each one vying for a piece of our attention. If our attention is too full the unnoticed thoughts burrow themselves into our subconscious waiting to be projected at a later time.
For me, the most disruptive thought bombardments I have experienced have usually resulted from relationship; specifically with someone I have been sexual with and emotionally attached too. Here is a 30 second window: "She did this or didn't do that; what does it mean? Why hasn't she called? Should I call her? Is she the right girl for me? What about this other girl, maybe she is a better match? What a bitch. I miss her. Mmm… sex that one time was hot. Is she sleeping with someone else? Should I open up and tell her how much I care about her? Maybe I should be more aloof?" Now repeat over and over and over again…no sleep for you… forget about being effective at work… your heart is slowly being crushed in a negative spiral of thought.
Thoughts related to relationship issues are especially disruptive because they are so closely tied to our emotions. But, even when it's not so obvious, our thoughts are always connected to our state of being. This is why being aware of our thought-feelings is so important; instead of being at the subjective mercy of our stream of thought, when we are aware we can objectify our thought feelings and respond or not respond appropriately.
Unfortunately, our "monkey mind" is patterned and habituated to run constantly and unabated. It is not helped by the fact that in our modern society, our mind space is under constant attack from external information and messaging. The only way reclaim our mind space is with a conscious practice that silences the mind, in other words, meditation. For many, the word meditation connotes Buddhist monks, hippies and new age yogis and that is unfortunate because meditation is probably one of the most beneficial tools available to humans looking to develop themselves (and improve their lives). Meditation allows the brain to rest and renew itself, it helps us recognize and objectify the bombardment of thought-feeling running through us, and it helps us tap into intuition as a way of knowing. In short, it helps us develop as human beings.