I've done several solo trips since 2006. Sure, you feel a bit odd at first with all the families and kids around. After a while though you just start enjoying everything. Especially the fact that you can do whatever you want when you want it.
Here are a list of some of the good things about going solo...
*The top thing is you make your own schedule. You don't have to get anyones approval. You can wander around doing nothing if you want. Who's going to tell you not to?
*SINGLE RIDER LINES!!!!!!!!!! I still remember riding Expedition like 4-5 times in a row while the same groups were still going through the lines. Even FP can't beat it!
*You're the only one using your hotel room restroom (at least I hope I am
). Makes getting out the door faster.
*Getting a seat on transportation is easy. I don't mind sitting next to strangers; using public transportation does that to you.
*Dining is easier. The wait staff doesn't usually mess up single orders, and the restaurants always have 2 seat tables or a bar to sit at.
*More space in the hotel room. I get to use the other bed to store stuff!
As far as doubts on going solo...
*If you get lonely just look around; there's always someone to chat with. You'd be surprised how much people love to tell you about themselves
*Want a picture of yourself? Ask a castmember or a friendly traveler. Haven't been turned down yet. It's also fun to volunteer to take pictures for families.
*Don't like eating by yourself? Find a restaurant that's busy, or sit outside if you can. Gives you lots to look at. You can always chat with the wait staff if they aren't too busy, or the bartender if you're at a bar.
*Worried that people might stare at you? They're to busy enjoying themselves or fighting to get through their 'vacation' to worry about you.
Well, that's all I got. Not sure if that helps, but hope it does.
However, late December when the official school holidays are in effect its too crowded with unpleasant and unhappy type folks (families with tired kids, parents on a short fuse, crying babies, etc.). I'm an empathizer so unhappy or unpleasant folks wreck my carefree kid-again experience. Did the Christmas and New Years holidays once, but never again.
and only remember getting out of the car at the end. Anyway, I suggest waiting in the rollercoaster queues to enjoy the theming, then whimping out before boarding if necessary.
You could tell the entire time she was dying to leave. I never leave Epcot until after closing, but was a good sport & sacrificed for the sake of her sanity (and mine). I usually like to stick around & soak up the atmosphere in Future World after dark. (I know, I know, it's not all about what I want). 
we left. Seems I'm the only Disney-parkaholic in my family. My sister, brother-in-law and their kids visited WDW planning to spend a week there. After 3 days they felt too bored to stay any longer and left never to return (my niece and nephew are now adults). Solo is the best way to really enjoy Disney parks.
