In the last two decades self-help and self development books are filled with advice telling you that in order to achieve your goals you need to think and feel positive. Real world is not functioning like that. If you try to be only positive all the time, the more you will become negative.
The nature of your mind is such that it actively focuses only on what you think. For example, if you say »I don't want this« only that will happen in your mind and your perceptions.
In other words, »I don't want negative«, you will see only negative. As a result of »wanna be positive« attitude, you might become easily frustrated by other people because you become much more susceptible for their »negative« behavior towards others, towards you or towards nature or something else. As a result you became angry, anxious, empty and start slowly withdrawing from the outside world closing yourself. This is often the result of »positive thinking« myth.
If you want to look at life only as negative or positive, it only means that you want to distort the reality.
It's obvious that thought precede emotions, so your thinking process definitely does something to your wellbeing. Everything that is happening in existence has both positive and negative side and it's only doing its purpose. It's the only way the whole existence can function. Try to rid one half of your body and see how you will function – not very effectively and it can become frustrating. You need both sides of your body to maintain balance and be effective. Same applies to your mind.
Trying to rid all the »negative« is futile and recipe for depression. It has the same crippling effect as trying to get rid half of your body. You want to be whole, not half. Balance inside your mind occurs right in the middle between positive and the negative thinking. When you hit that middle point you have no negative or positive emotions about outside or your inside world. You feel equanimity, you are centered, poised, have clarity in your mind and your thinking, your heart widely opens and you are in deep state of true gratitude.
Gratitude is not something you feel when something »good« happens to you and you can be grateful for that. True gratitude is a state of being, where you are completely grateful also for the »negative« things in your life and not only the »positive« ones. It is wise to »discharge« all events in your life, which were perceived as negative or positive. You simply do that by reviewing it, searching for the other side and becoming conscious of it. If you are not balancing yourself daily, the outside world will.
Ofcourse, positive & negative thinking both serve. When we are down and depressed positive thinking help us to rise back up. And when we are too high up and fantasizing, making pies in the skies, some critical thinking is needed to be able to put us back into reality.
Balance thinking is your key to be present, to expand and to grow. Our myths of one-sided life keep us from recognizing divine order and perceive life as it is. Accept the situation as it is and see what is best you can do about it to the best of your intelligence, activity and capability. Embracing both sides of life help you to be prepared for the real challenges that you face and to do great things in the world.