[Your Name] [Your Address] [City, State ZIP Code] [Date]

Dear Friendship,

I hope this letter finds you well. I am writing to express my gratitude for your presence in my life. You have been a constant source of support, laughter, and comfort, and I cannot imagine going through life without you.

As a fifteen-year-old, I am going through a lot of changes and challenges, and having you by my side makes everything easier. You have been there for me through thick and thin, and I appreciate your unwavering loyalty and kindness.

I cherish the memories we have created together, from our silly inside jokes to our deep conversations about life. You have taught me so much about myself and the world around me, and I am grateful for every moment we have spent together.

I know that as we grow older, our lives may take us in different directions, but I want you to know that you will always hold a special place in my heart. I look forward to creating more memories with you and experiencing all that life has to offer.

Thank you for being my friend and for all that you do. I am lucky to have you in my life.

Sincerely,

[Your Name]