In our thoughts, there is no ‘thing’ per say. There is only ‘nothing’. What truly exists is the Now. But the Thought of something can also manifest in the now but its a thought. Not a thing.
The problem arises when we think of thoughts as a thing and later when this ‘thought-thing’ has become so substantiated, that it becomes seemingly solid to the mind that is thinking it. Only because through repetition, this thought things becomes a relatively fixed structure within the mind, seemingly fixed as an everyday thing like your house door or house window.
At this point its important to remember you were its creator and u too can be its destroyer. Destroy this ‘thought-thing’ by realising its impermanence and transientness as a flowing thought.