It’s okay,
Take a deep breath, close your eyes because it will end when you let it. Your stomach is churning and your chin is twitching as you hold it all in, but it's okay. Let it out, because it has no where else to go. Let your tears drop, let your voice grow hoarse with sobs or screams. Your fingers become sore from tapping angrily at the keys, but that's okay too. Let the calloses grow frim and let your soul harden from experience.
Old souls are not ones that have lived many lives, they are the people who have visited the darkest parts of themselves and come out kinder. Feel those hard feelings and understand them. Look at that broken person in the mirror and memorize her. Remember what dried tears look like, how puffy and red her eyes are. Most importantly, remember the look of desperation. Know it well in your reflection.
Now use it all. Use the tsunami of emotion to create whatever you want, that creation may not be perfect or the most popular or the best written, but it is you. Nothing and no one can take it from you and those who decide to experience it will learn something about themselves through it. Whether it be good or bad you have put something out there that will impact someone's life. Even if it's the most minute thing, the smallest detail or just a random person bored on the internet, it's out there for someone and it will find them at the exact moment they need it most.
Suffering is not a curse or a misfortune to put you off life, it's a challenge to live it better.