I used to be the only developer at my company, responsible for all of our internal web software and outward facing web software, and developing all custom code.

I used to be the only developer at my company, responsible for all of our internal web software and outward facing web software, and developing all custom code. I had 10+ projects going at any given time as well as catching any bug reports/questions for any of our internal web software. I reported directly to the CEO. I coped with this as long as I could fighting through burn out until I finally let him know we needed to expand the team. I was buckling under all the tasks. I spelled out clearly how it was far too much for any one person to handle. We've slowly over time expanded the team until we now have 5 developers, which is still less bandwidth than we want but it makes things a lot more manageable, because we now as an organization accept a more realistic view of what we can do with the team we have. I would say try talking to your manager about the reality of your situation. Have a real conversation about your concerns. If they go unheard or nothing comes of it, then it's probably time to move on.