People who have never gone solo often fear or dread it a little - and in the end, probably more than 95% end up loving it. I've been going to Disney World since 1971 when I was just a tot with family, and had never gone solo until about 2006 or so. It started out when I was going with family, but I wanted to do something else, so I'd split off and go to a different park on my own, meeting up with family later for dinner or evening. It was so freeing and relaxing to not be on anyone else's schedule or catering to their preferences. Our family trips often were groups of 8-12, with friends and neighbors staying in nearby rooms, so there was a lot going on.
Somewhere along the way, we were planning a trip with some family and they had to cancel - I decided to keep the reservation and go on my own...my first official solo. On that trip, I didn't wake early - I slept in, did breakfast, relaxed, started my day close to noon, strolled the parks with no fast-passes or reservations or plans - just picking rides if the lines weren't bad, stopping at quick serves or bars for a snack or drink, chatting with others at the bars, left early to do some resort hopping, brought my tripod and camera gear to do some long-exposure night photography, staying well after park close to catch empty rides and scenes. It was bliss - and from that moment on, I regularly booked solo trips in between the family trips.
I also started to mix in some trips with just a friend - as some of my friends who had come along on the big family trips heard how much more relaxing the solo trips were, and they wanted to experience the laid-back pace with no planning - all of my friends who came with me for those twosome trips ended up loving them - some who had really not been enamored of Disney anymore (fast passes, planning, reservations, rope-dropping, running around frantically to hit all the rides - they were just tired of the rat race)...not only do most of those friends try to do 1 trip a year with me the 'new way', but several now regularly do solo trips themselves.
My mother and stepfather both passed away in 2023, and they were often the central planners of the big family trips - so the dynamic changed and my brother and his now-grown 3 kids no longer go to Disney often - so there are no more family trips - I still go at least 4 trips a year, generally every 3 months, and I do a mix of trips with a friend, solo trips, and once every 2 years a big group trip as part of a photography event, most of them I've known now for 15-20 years. The trips with friends are great because they've all signed on for my relaxed style - sometimes it's a fun guys trip with bars and live music, sometimes a nice more intimate trip with a female friend with signature restaurants and scenic walks. But I couldn't imagine a year without at least one solo trip - roam resorts, do photography, read books at the villa - sometimes I may spend 4-6 hours of the day in a park, hit one or two rides, and the rest of the day is cruising around to various resorts on boats, hitting bars and seeing live music or shows, do some wildlife and bird spotting in the mornings or early afternoons.
BTW - Old Key West should feel incredibly safe on your own as a single female. The atmosphere is so family and laid back, lots of people walking around, most will say hello as they pass. Disney's bubble in general is very safe for solos, but some big tower hotels with long hallways, or parking garages may play on some people's fears (even if they're perfectly safe)...Old Key West is so open, well lit, and the small low buildings with individual entrances are all very welcoming and safe-feeling.
