Once I started quilting seriously, I acquired fabric that no longer "works". I donated those "blunders" to local quilt groups. Just tossed them into plastic bags and never looked back. This process helped me to control my fabric and spending. When NM opens up again, I may do this again. Maybe this will help you to get a handle on what you have.
I've watched hoarder shows and they all started with three containers...keep, donate, toss. I also noticed that she/he had to make a quick decisions and can't change their mind. Start in a corner of the room, work your way around. Set a timer to work. Maybe only 30 min to start. Soon you will have a beautiful sewing room you can enjoy.
Keep your eye on the prize! You can do this and we are all here to help you to stay motivated.