To make matters worse that is the teaching of some spiritual leaders. They pile on the guilt by telling them that if they have any negative thinking they are not being spiritual.
However, we live in a world of dualities. Light and Dark within and without. Balance is important. It isn’t the negative thinking that pulls us down, it is focusing on it without transmuting it into something good.
In other words, if you have a negative thought, follow the line of thinking back to the source of it. Finding the root cause shines light on the issue you need to heal. Hard work, I know. At times you need someone to help walk you through it. Other times, you wade through it with the help of your guides and angels.
Situations come in your life for you to learn from them. If you find yourself just complaining about them and continuing to complain about the same thing, perhaps you are not learning the buried lesson. Ask for the Angels to illuminate that which you need to see, so you can continue your Ascension process.