I'm going to skip over the "find a hobby that gets you outside the house" because I assume you will have thought of this and/or others will elaborate in the comments.
So my attempt at novel advice is not to sleep on online relationships. If your rural community is too small to support a group in your niche interest, find a group online. Be active in the group, asking and contributing, joining and volunteering. You may find it's still 100:1 people you interact with to people you form any sort of lasting relationship with, but that's not really any different than IRL.
One of my sister's longest lasting friendships is with someone she met playing an online Horse Girl^TM game in the 00s. The game has been defunct for a decade, but they stayed friends. They only met in person for the first time when the friend was getting married. You never know when our weirdness vibes with someone else's weird; it's a beautiful thing. She values that online-origin friendship just as much as any IRL-origin friendship.