My friends have been getting on my case lately for chronically changing my mind. I may say I'll go camping with them, or have them over for halloween or go out drinking with them but then, later, I'll tell them to "nevermind". Granted, I do my best to give notice of my change of heart well in advanced, they still seem to take great offense. They take it personally. I wonder why? Feelings change. Why can't they understand that? How am I supposed to know if I'm going to want to go on a field trip a week in advance. I do what I want when I want. I would never get mad at someone else for ditching me (again, as long as he gives decent notice). I don't like being in demand.
I think it's is a habit that is common with stoners.