When you are creating art, you are also developing a relationship with this raw form of self-expression. Sometimes you allow yourself to experiment without judgement, other times you might inhibit your self-expression and tell yourself you're "not good enough", and you might also begin to understand yourself better through the art content you are producing - your lyrics, your artwork, your compositions, characters in your novel etc.
It's important to take a step back and acknowledge the privilege in having this window to self-knowledge and self-awareness. Just like dreams can show us many things about our subconscious, our relationship to art-making can reveal what you think and feel about yourself at any given moment. As an artist and creative person, you are able to understand that you hesitate to write the next novel because you might feel your thoughts are not worthy of being told, or that are not recording the songs you have in your head because you are constantly doubting and questioning your choices, or that you do not feel comfortable talking to promoters and agents because you don't see yourself as likable.
However, it is equally and maybe more important to identify the powerful effect of this parallel relationship and to understand when and how it interferes with your creative expression. Art-making may illustrate and put the spotlight on some of your internal struggles. Luckily, this can become an excellent opportunity to confront any vulnerabilities and attempt to build on the kind of relationship you want to have with your art. You probably want to respect and encourage your art-making moments, to forgive mistakes and to learn from failures. You most likely want to protect this relationship from harsh criticisms and to spend time cultivating and nurturing skills and strengths. Pay attention to your relationship with yourself, how creating art brings this out, and begin to think about the kind of relationship you want to have.