Burying your phone, diary, and bass while telling your friend it's your corpse; yeah, that's suicide shit. The other option is actually less realistic. Suddenly giving up on your friendships, moving away/changing your adress (since she was missing and all her friends searched for her), throwing away your personal possesions, probably dropping out of college (since she's 22, it's likely)... all that, to make a girl MAYBE want write songs again? I can't pretend that's the more realistic option here, unlike some people in this thread. To only other option is that she had some reason she had to leave literally everything behind anyway. But judging from the "Will you never leave me? No matter what?" comment, even that seems unlikely.