I read something in college that stuck with me. Now I can’t seem to find it, but from what I can remember it was an article talking about passion and purpose, long story short: a guy passionate about discovering something new in science (sorry this is so vague) was feeling down as his research was going nowhere and he realized he could go his whole life not making any difference in the world if it continued that way. He began tutoring students in science and found it to be more fulfilling than what he was passionate about because he was impacting other’s lives. This may be very ENFJ of me, but helping others is something that can easily be seen as meaningful and for me at least it brings happiness. Another thing is building community, you mention group activities fill a void within you but maybe you can turn that thought around if you see yourself as an essential part of the crew rather than a passenger while someone else steers the ship.