Explore your environment
As a rule, the environment is a reflection of the internal state and thoughts. And vice versa. Evaluating your environment, perhaps you will understand that bad thoughts are formed due to the fact that everything around contributes to this. It can even be dirty dishes.
But people are especially important that they are around you. They have a very strong influence on how you think and what you think.
Remember that it is you who choose your environment. If it interferes with development and movement forward, it will be extremely difficult to change habits and improve oneself.
Books
"Change your mindset - and you'll change your life" by Brian Tracy.
"Flexible Consciousness" by Carol Duak
"Genius for the Order" by Mark Levy
"Rules of the brain" John Medina
"Invincible Mind" Alex Likerman