I guess writing is still a poor form to record the whole spectrum of human emotions. Until we find a way to do that, context would necessarily have to be lost.
If only there was a way to make a person relive the same "memory" or "experience", like a Pensieve[1]
Why stop there? Instead of saying "until we [someone else] find a way to do that," why not explore what that would take?
What does the research tell us about how we feel? How is that different across genders? Across personality types? Across cultures?
How can we represent that? What sort of accuracy matters? Should it be relative or absolute? Does it matter? What will we be using it for?
How can we record it? How much can we trust self-analysis, like diaries or mood questions? How much can we trust biometrics? Is that dependent per-person or can we generalize?
What sort of biometrics would we need? How long would we have to wear them? Where? Power? Fashion? What about on the beach, can they survive sand and salt water and 110 degree F weather? What about military use, can they survive high-pressure sand and persistent sweat and the very different bodily reactions that someone in a firefight goes through compared to a soccer mom?
What is the goal of an emotional recollection? To understand it yourself? To remind yourself? To reminisce? To convey your emotions to another? To allow another to find something similar in their own recorded memories so they can empathize better?
Don't stop at fiction or wait for someone else to make a web service for it. This is something that can be designed and built today. This is something that could have been designed and built a decade ago.
If only there was a way to make a person relive the same "memory" or "experience", like a Pensieve[1]
[1]:http://en.wikipedia.org/wiki/Pensieve#Pensieve