Short backstory:
I've been working for my current company for a few years as a developer and IT Support\Specialist which includes a lot of calls, help-desk duties along the developer part of the job. This job includes a lot of outside of job hours calls and interventions as well. I am satisfied with my salary and the collective inside the company is great. I love what I do.
The problem:
I have noticed my work efficiency slowly dropping over the past year. It seems like I find less and less joy in what I do and its a bit distressing. The last couple of weeks have really been stressful and I feel I overworked myself a bit. I had a 2 week vacation where I tried completely ignoring and not thinking about work which worked relatively well but when I came back to work I found not much has improved. I often find myself spacing out and losing focus and/or getting distracted a lot. Again, the most distressing of all is that I am slowly losing the joy I felt for this job.
I have done a bit of research and I must say resigning or taking a long time off the job is not a viable option as I am not stable enough financially to afford being off work for an extended period of time.
Update:
It is a small team of 3, for privacy reasons I'll use fictional names Bob(me), Steve and Tony. Here are our roles:
Bob - Developer and Support
Steve - Developer (knows enough to do a Support role but is unwilling to)
Tony - Support (not a developer)
The structure is such that if I fall out of any of my duties one of the others gets overburdened or worse(like in the scenario where I took a vacation), nothing(or almost nothing) gets done until I am back.