If you've been going through your life living out comfortable routines, that will all get shaken up in this friendship. The way you usually do things will fly out the window, and you'll be called on to change. Things will have a way of spinning out of control of their own accord.
Your amigo will go through big changes and dramatic emotional displays, while you'll be busy trying to resist the changes and hold on to the status quo. You'll both have to dig deep and figure out where the incompatibility is occurring. Are they pursuing a career that seems unstable or even unseemly to you? Or do they just have a much more varied and transformative emotional life than you do? Wherever the differences lie, if you can look at them honestly together, you'll be able to find out how to learn from each other so that each of you can grow as individuals.