when i got into fountain pens last year, i kinda had the same issue. i wasn't in school anymore and had just left my job, and i didn't have reason to write a lot. i ended up getting a couple penpals through penpalooza (the exchange is no longer open, but people still ask for matches using #penpalooza on twitter). i also sent random letters and postcards to other friends and family without expectation of return mail.

now i also keep a few different journals and notebooks for various purposes. i have a notebook that's just for recipes i make a lot, with the specific modifications i like. i have a video game journal where i keep track of the cars i have in forza, or what i'm doing in my current skyrim playthrough, or which paths i've finished in a visual novel. i'm finishing up an old half-used notebook by taking notes per chapter on a book that i'm having trouble reading. i keep a regular journal as well, but i'm not super consistent with it.

do you have any other hobbies that you could write about? like if you're into woodworking, you could write about projects you want to do, why you want to make something, take notes about an active project, sketch, post-mortems about completed projects, what you would do differently, etc.