I am (re)reading one of my favourite books at the moment: Fight Club. It was also made into an excellent film in 1999, but really it missed the essence of the book. Some people think the book is negative and nihilistic, but they have missed the point…
There is one bit in the book where Tyler Durden, the antihero of the novel says “you are not ….” And then lists possessions.
Very true, but I think you can extend that even further:
You are not your behaviour. You are not what you do. Some people call themselves “depressed”, they are not, they someone who is doing a behaviour called “depression”. Some people call themselves a “smoker”, they are not, they someone that does the behaviour called “smoking”.
You have to divorce your behaviour from your identity. You are not what you do! Some people are very attached to their bad habits because to them that is who they are, it defines them and if they don’t have it anymore, who would they be?
Let go of your behaviour, realise it is just something you learned to do. And you can learn to do something different, or just forget to do the behaviour (how many things have you learned at some point but now forgotten – trigonometry anyone?!)