Member Rara Avis
"Disappointment" implies expectations, Chris. You are responsible only for what you do, not what others do, and the latter necessarily includes what they allow themselves to "expect." If they are "disappointed," that's their problem, not yours.
Really, can you think of even a single reason why anyone should feel it's necessary to live up to someone else's expectations? Set your own standards, accept only those standards, and the only person you need fear disappointing will be yourself. And those are shoes we all have to wear occasionally.