I don't think it's boastful or narcissistic. Because it's about her way of trying to deal with it. She's trying to pass it off like, "so what? It's no big deal." When it obviously is. She's means it not as "I'M SO AWESOME" but as, "this is how I can keep moving on". Music is her real passion, and she's saying so what I'm still a rockstar because it means that she still has a way to move on with her life, and something else to live for. I think it's a pretty strong statement.
I don't think it's boastful or narcissistic. Because it's about her way of trying to deal with it. She's trying to pass it off like, "so what? It's no big deal." When it obviously is. She's means it not as "I'M SO AWESOME" but as, "this is how I can keep moving on". Music is her real passion, and she's saying so what I'm still a rockstar because it means that she still has a way to move on with her life, and something else to live for. I think it's a pretty strong statement.