It's not uncommon to have a longing for a friend who can be there for you like a shadow, always present and never leaving your side. Additionally, it's important to acknowledge that no one can be your shadow, as everyone has their own life, priorities, and responsibilities. It's important to maintain a healthy level of independence and self-reliance, even in close friendships.
Rather than focusing on finding a friend who can be a shadow, try to cultivate strong, supportive friendships by being open, communicative, and compassionate. Invest time and energy into building meaningful connections, and be willing to give as much as you receive.