Workplace Headnoise

I have been in the same job for 12 years, I left in 2022 to try something else it didn't work out. I went back to first job on the word to my boss that I wouldn't be managing the full house fit outs and I would be more so bouncing around the other tradies helping them on their jobs. This was great for a year. I was asked to run one big job and I said yes this will be fine it has dragged on for 4 months and it's not Evan half done yet. Now I am getting wind that a few people are leaving or changing positions and all I can see is that I'll be the only one that's actually good enough to control the big jobs and I don't want it at all. I feel like I'll be forced into it cause others are getting off tools and people are leaving. He always wants me to be a foreman but how can I be if I'm always out on the big jobs for months on end. He will have to hire more people but new people don't last over 3 weeks at my work?? How do I address this. Is it time to leave ?