Elizabeth Weber in Confessions of a Prodigal Volunteer articulates why it is difficult to find the balance between volunteering and participating in church life:
I knew I’d erred in gravitating toward roles that, although worthwhile, didn’t feed my spirit. I’d come to care too much about the work, for a mishmash of reasons—ego, certainly, and strong convictions based on a by-now prodigious institutional memory. A sense of earned power—that occupational hazard of intense volunteer commitment—also tethered me. And if I set the work down, I feared it might lie there a good long while (horrors!) before others picked it up.
As Weber points out, volunteering in church requires that you not only serve others but serve your own spirit. It's just as difficult to navigate as paid work, but is a practice that we don't always pay attention to. Many of us volunteer until we are burnt out.
A key element of long-term volunteering is being mindful of your own needs as you volunteer and not just the many needs of others. You might like to read Volunteering 101, Why Volunteer, How to Know When Not to Volunteer, and Beyond Capitalism for information on other economies.