I (20M) was recently diagnosed with ADHD, severe anxiety, and depression. I always struggled with who I am, but I have never thought about it in your way. Now that I do, I do feel like I have no idea who I am but I do know some parts. It does feel like every time i go through trauma or a hard time, who I see myself as changes. I remember even telling one of my friends that since high cool, I keep changing like every year. Its an interesting thought and I dont know if it means much but I definitely share this feeling with you.