Solving problems isn’t hard. Once you know what you’re trying to achieve, then for most problems you can see a few ways to get there, so it just comes down to choosing the best course of action and following through.
Problem definition, on the other hand, can be damn hard.
When you’re facing some problem and it’s driving you crazy, sometimes you’re best to stop and wonder whether you’ve really defined the problem accurately. What are you trying to solve? What is the original problem? Why is it such a problem? How else could you frame it? What description would make it more tractable?
If you can get the problem definition right, your chances of finding an optimal solution are greatly improved. Don’t keep soldiering on down the wrong path, refusing to acknowledge that failure is also an option.