Rejected from Dream Job

Today I was rejected. It was a somewhat unique job and I was sure it would change the trajectory of my life. I was also sure after my performance in the last round (where it was down to me and one other person, and I was told to just be myself since I had appeared somewhat nervous in other rounds) that I would not get the job. I choked. I was nervous. I wasn’t focused and confident. I wouldn’t have hired me. So I wasn’t surprised. It’s just sad to me that my personality, experience, and education were perfect, but I couldn’t hold it together for this last round because of confidence. I am sometimes a very confident person, and that’s what I showed up as in the first two rounds. How do I show up as that person more often? More importantly, how do I bring that person up on command?? Also, what do I do about this rejection? It *almost* feels better than others because it wasn’t about me, since I wasn’t even acting like myself – I was just an idiot. By the way, there’s a very, extremely, tiny sliver of myself that’s proud because I’ve never applied for this level of job.