I am a 47 year old guy and this is my 3rd solo trip to WDW in the past 4 years. I also lived in CA and went to DL solo over 100 times.
I *love* going solo. I can do what I want, when I want. I can also choose to meet friends or go alone the whole time. I did a 9 day solo at AKL and it was wonderful. Everyone treated me like royalty and was never ignored or pitied because I was alone.
I planned out my days and if something didn't go right or I simply changed my mind, no problem. I could adjust on the fly and not have to worry about other people's disappointment. I made the ADR's for places I enjoyed, or thought I would enjoy, and the times that fit my schedule.
The rides are just as much fun solo as they are with others. Last year, I met up with some great people from here for the 'One More Disney Day' event and it was a blast to meet them. We hung out a little, but we all went our own ways. I enjoyed the interaction, but I was still doing a solo trip.
Sometimes there's a bigger benefit to going solo... I wanted to eat at Via Napoli, my favorite restaurant, and I didn't have an ADR. When I went up, the wait time was 45 - 60 minutes. However, all the parties before me were 3 or more people. A table for 2 opened up and I got it because I was a solo. I only waited about 15 minutes.
I also bring my nintendo 3DS into the park with me and I can play games while waiting in line.. or I'll read a book with my iphone kindle. I also enjoy people watching and will just sit on a park bench eating a dole whip and watching the crowds go by.
A solo vacation, no matter how busy I make it, has almost always been more relaxing than a vacation with family or friends.