Thank you for sharing your dream. Dreams can often reflect our inner thoughts, feelings, and experiences. Here are some interpretations and insights based on the elements of your dream:

1. Bookstore Setting: A bookstore often represents knowledge, learning, and the discovery of new ideas. This could signify a desire for personal growth or the search for answers in your waking life.
2. The Storm: Storms in dreams typically symbolize chaos, challenges, or emotional turmoil. The fact that you were aware of an incoming storm suggests that you may be anticipating difficulties or changes in your life.
3. The Grayish Man: The tall, scary-looking man could represent an intimidating challenge or fear that you are facing. However, his transformation into a helper indicates that confronting your fears or challenges can lead to support and guidance.
4. Your Coach's Role: Your investing coach represents guidance and mentorship. Her disappearance might reflect feelings of uncertainty or a lack of support during challenging times. The fact that she communicated through messages suggests that the support you seek may not always be immediate or tangible.
5. Floating in the Bubble: The bubble you used to navigate signifies a desire for safety and protection while facing life's challenges. Your willingness to move towards the storm instead of away from it indicates courage and a readiness to confront your issues.
6. Going Through the Storm: The notion that you must go through the storm to reach the clear skies suggests that facing challenges is necessary for growth and resolution. It implies that you are on a journey of overcoming obstacles and that the struggle will ultimately lead to clarity and peace.
7. The Book with the Gray Cover: Receiving a book after coming through the storm may symbolize new insights, wisdom, or lessons learned from your experiences. The gray cover could relate to the uncertainty or ambiguity you feel about the situation.
8. The Thing on Your Wrist: This item may symbolize a connection to the challenges you've faced. The reassurance from the bookstore employee implies that you have gained what you need from the experience and can now move forward without additional burdens.

In summary, your dream suggests that you are navigating through a period of challenges but are gaining insight and support along the way. Embracing your fears and facing the storm might be necessary steps toward personal growth and clarity. Reflect on what you can learn from these challenges and how they can lead to your development.