Try the free version of Swift To-Do List AND review the free articles on the site. Those will explain how you got into your situation and how to tackle your problem. One cause may be that you have more items than you can do. Another may be that they're not prioritized by (importance / urgency) or organized / grouped into projects.
The program is not free or inexpensive but you have 30 days to get organized and when the time is up, you can always export you todo lists into something else.
You'll learn a lot from reading those free articles and the free newsletter. Below are sample topics .. One of them is "Is your to-do list impossible to finish?"
That sounds like your problem. Other topics include ..
>"Custom Task Priorities" and "Preserving knowledge and retaining information,"
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>"How to join two different task types (or priorities, contexts, etc) in Swift To-Do List," "The next actions and prioritizing," "Color your tasks,"
The main page shows the features along with a video showing how to get organized in 5 minutes. One secret is the ability rapidly input tasks and subtasks all at once into a window. The program sorts all that out, creates tasks you can attach notes, too, set properties, etc. You can also attach files to tasks.
Here's ultimate bearbones ...
>"So many power users try dozens of complicated todo list software applications, only to go right back to their trusty todo.txt file" -
> Article Excerpt - "Todo.txt stores your tasks in a simple text document, and I’ve been using it for a year now. I honestly wonder why I ever used anything else. -- To-do lists don’t have to be complicated: people literally use pen and paper to keep track of their tasks. And yet most modern to-do apps are bloated nightmares."
You might also try the free 30-day trial of Swift To-Do List. It has an excellent UI that lets you input tasks quickly, organize them if you like, add notes and mark them as done quickly.
Ignore the UI features you don't need and simply use it as a barebones todo list program accessible instantly via hotkey. One useful feature is multi-task entry where you can type many tasks at once.
I use Swift To-Do List. http://www.dextronet.com/swift-to-do-list-software
I haven't needed the pay version's features, nor has my disturbingly organized co-worker who found it. It can handle multiple lists pretty simply, which we find useful.
BTW, I have nothing to do with the company.