Short and sweet today!
Struggling with organizing is very common but most of it is mental blocks.
Be honest with yourself about why you cannot get your head around organizing and prepared to work through some difficult feelings to get you through to the desired outcome. This is why working with someone is important and beneficial, someone who is objective, non-emotional, non-judgemental and can help challenge you to see around your mental blocks.
If you are keeping things out of guilt but space, time and energy are more important to you, then remember that nobody knowingly wants you to feel guilty. So if you are holding onto things from an elderly or deceased relative, remember that any guilt you feel from releasing those items are not from that relative. They wouldn’t have given you something to have negative emotions, most gifts are from love. So can you lovingly pass those items along to another family member who would love them, use them, or put them in the hands of a stranger (either through donation or selling them) that would make that stranger happy. Imagine eliminating negative feelings in the world just by moving objects around to people who will love them.
Motivation may also be hard to muster when organizing. I suggest printing a picture of the room like you want to organize and put it up in that space as a visual reminder of what your end goal is. When you struggle to get started on organizing, look at the picture and remember baby steps will get you to the end goal of organized, while no steps will get you nowhere, except for your current state of stress and anxiety with your space.
So go tackle a small bit of a bigger project, think about what you are thinking as you do it, so you can accomplish the task and feel good and proud of yourself!