I spent 5 days this September on my first solo trip and I LOVED every minute. We don't have kids and my husband has paid his Disney dues over the years, but I am always the tour guide when I go with anyone. It's not something I mind doing, but this unexpected freedom was amazing. Yes, my people weren't there to share things with, no one cared what I did or how I spent my time. Interestingly, the young people at Fuel in the Dolphin were so friendly, I told THEM about my day.
The reality for me is that Disney will always be better with my family and friends. It is also true, however, that you are as alone as you want to be. No one thinks it's weird that you're the only one in your party for rides or meals; quite literally, no one notices. I proudly wore the First Trip button to which I'd added "Solo." People commented, asked what being on my own felt like, and my answer, without hesitation, was always "Wonderful."
To anyone contemplating a solo trip, I say try. Doing so works or not, and neither choice is bad because you're still in Disney World.