Product development/management is tough as hell. Thankfully there is an amazing community of practitioners. The book, Product Leadership (website, Amazon), has so many nuggets of wisdom encoded in it. Check it out :)

Here are some quotes I found noteworthy and strive to commit to my DNA:

• Great product people will ask questions about the product, the market, and the business. Not only this, they show an interest in all aspects of the team they work with, from unified vision to individual communication styles. Understand that producing great products can be difficult and frustrating, but still want to do the work.
• Ultimately, the job of the product manager is to get results through other people.
• What is common in high-performance teams is that they are cross-functional, collocated, and autonomous.
• Developing processes that remind teams of the customer and their needs is a big part of the PM's role.
• Empowered to change the company's vision, strategy, culture, and processes.
• Need to gain authority through my actions and leadership skills, not my role.
• Not just how much I do, but also how much I enable others to do as a leader. Whether that's as a product leader, sales leader, marketing leader, or other. 
• What keeps product leaders awake at night? Prioritizing roadmapping decisions without market research, being stretched too thin, dealing with executives, hiring and developing talent, and aligning strategy.
• Stakeholders clouding decisions without evidence can derail even the most well-thought-out plans.
• An idea that has no data, evidence, or testing behind it will not hold up against an idea that has the weight of research and testing behind it. Voting and ranking exercises add visibility and expose weak perspectives.
• Promise to solve problems, not build features.