I'm >>10053519 and I believe I'm neither.
I have a friend who flakes on things all the time. And with shitty excuses on top of that.
Yet, they're the one who used multiple of their afternoons to help me do better on school. They also took kittens from the street and treated them until they found a home, and did it more than once.
Just saying, life isn't a binary thing. If you choose not to connect with someone solely because of that, you might be missing a good friendship otherwise. Plus, as the anon explained, there were things happening in her life that made her rethink the trip. It wasn't out of nothing.
Good luck, anon.
If she ends up not going, don't let that ruin your trip. Meet people, go to maid cafes, buy cute clothes in Shibuya and Harajuku... and who knows, you might make more friends there who you can introduce to her later!