I am super-flexible when I initiate the change. Which is something my inner circle is very well aware of. I actively encourage them to 'manipulate' me into thinking it's my idea when they need to change a set date/time for an activity, since it's less stressful for me and it's a whole lot easier for them to handle me.
An example: We decide to go to the amysement park next town over. We figure out the train schedual and decide to meet at the train station at 9:00 AM two weeks from now. Two days before they realize they have to do something and need to push the meet-up to 10:00 AM. They'll call and say 'Hey, there is a direct train leaving an hour later', to which I'll naturally respond 'Let's take that one instead!', because it's less hassle for me to deal with strangers gallopping around on an off the train. For some reason I can't explain, that works a lot better with me than if they called up and said 'Hey, there is a direct train leaving an hour later, let's take that one instead'.
Also, for me it has to do with level of comfort. Some people I can hug, most I can't. Some people I can hug under certain circustances, but not always.
At work, I hate it when I get into the office and they tell me that so-and-so is sick, you need to do this instead of what you usually do. It is not about being able to do the work, it just shorts out my brain. On the other hand, I can deal with just about any contingency and not miss a beat (I work in aviation/transportation so tail swaps, technical issues, delays, re-routings, extra flights etc are quite common).
Maybe the vcommon denominator is, expected changes, or changes I feel in control of, I handle well. Changes sprung on me out of the blue, not so much.