You're only 20 - you're not 20 and responsible for every action everyone you love takes. You're only responsible for you. You can't take care of others if you ignore your needs. You can't compensate for self-care by taking care of others. You're only 20. You don't know enough and that's ok. You don't have to know everything, you just have to cherish what you have.
I love you. You're loved. You're not going to find love after 50 Likes on Facebook, in that third office hour in one week, on Tinder just because that other girl seems to have found a good time which you think is love, nor in that quirky obsessive habit to reorganize your space.
I love you. You're loved. Do what you know best - being you.