You'll forget what you accomplished, what made you double over with laughter, and what mistakes threatened to derail everything -- only to teach you so much you'll eventually attribute much of your happiness to them.
Don't give up because life is different or harder than you expected. Just alter your expectations and plans as needed and expect that to be part of the process. After all, it's not so much about reaching the finish line as it is a matter of developing your skills and abilities and doing your best.
In the same vein as any work of art, appreciate plans for what they are and leave room for spontaneous creativity. What initially strikes us as a violation of or departure from the grand plan may become the focal point of the next.
Once we assess a person's current balance point and determine counterbalance techniques that they agree to employ, measure and adjust, we can create a life map to take this person from "here" to "there," wherever "there" is for them.