You have very well understood this important aspect of human nature. There is not a single moment when we are devoid of thoughts. If we take out some time for ourselves and think with a relaxed mind, we will realize that every moment our mind is filled with thoughts. These thoughts could be related to different incidents that one must have gone through or just certain random ideas and desires that one craves for.
So we can be sure that every moment something or the other is running in our mind. In your case, you have understood that how these thoughts bother us every moment. Not only you but also every other individual who need a relaxed and a free mind would understand the importance of a calm mind.
There must be some or the other way by which we can control our thoughts or our mind as a whole. Below are some of the ways which can help you succeed in this to some extent:
A long walk is a good one to keep your mind fresh, especially in some place where you can attain oneness with the nature. Nature is silent. It is not like human mind which is full of thoughts. This is the main reason why oneness with nature influences you and makes you feel fresh enough to sustain the thoughts that are bothering you.
Especially when you are filled with negative thoughts and thoughts that upset you or turn you off, try to think of ideas that generate positivity in you and divert your mind from the negative points or thoughts. For example, think of those small moments in life that made you happy. The moments which helped you develop or inculcate qualities like love, compassion and care are the ones which filled you up with positivity. It is because all these emotions are positive ones and are powerful enough to kill the negative thoughts.
Frankly speaking, the above two points that I have mentioned are ones which help you externally to get rid of negative thoughts and random thoughts that cloud your mind. These are effective but if not handled efficiently, these methods could prove as a temporary solution. The reason is that these are external methods to overcome thoughts. The main reason that your thoughts bother you so much is internal in your mind and if you try to apply external methods, how can you find permanent relief and content.
Meditation is the best method that one can use to overcome negativity and thoughts in general. When meditating, you are actually directing your mind towards a single positive idea or a thought. For example, when someone meditates for his/her God, he is trying to be one with the almighty. In this process, you start turning inwards to attain oneness with own self. When you turn inwards, you start becoming increasingly calm. Emotions like anger, hatred, ego, and false-pride start losing their grounds. You start developing the art of letting your thoughts simply pass away in front of your eyes. Imagine you see a person passing in front of you, someone whom you don’t know. You just saw him and nothing more. Such is the state of your thoughts when you meditate. You simply see your thoughts passing away without feeling oneness with them. Hence, meditation is the best tool to work on your overall being as it helps you develop every positive quality within yourself.
Thus all I want to say is that our thoughts will bother us only if we give them due importance. If we simply show a careless attitude towards them, as if they mean nothing to you then how can they affect you? So think over it.
Let me know in case you have any doubts related to the above points. There is always a solution to every problem. Just the right thinking and the subsequent action is required.