Dear Princess Celestia

Haven

This year I learned that you can always trust your true friends, even if one of them is Juan. And conversely, if someone is a known liar and you know they're trying to get something from you, maybe think a bit about whether they are lying to you to get something from you. No. However much you are thinking, think harder, damn it.

Your Faithful Student,

HavenPEGASUS

Anonus

What is this a reference to? MLP:FIM aside, obviously.

Misery

Well, duh.

Rottweiler

Dear Princess Celestia,

This year I learned love your enemies, do good to those who hate you, bless those who curse you, pray for those who mistreat you. Whoever hits you on the cheek, offer him the other also; and whoever takes away your coat, do not withhold your shirt from him either.

Your faithful student,
Twilight Rarity

Viani

Dear Princess Celstia,

This year, I learned to love again. To open my heart again once more, and share it with the one most important to me. I don't think I can live without her.

Your faithful student,
Lilium Rays

Yarrun XIX

sunn wolf said:

dear princess celestia,

i
am trapped in a torus of five dimensional space from which i cannot
escape. the solar winds scour my skin and make it impossible for me to
open my eyes for any period of time. when i do open them i can see the
very mouth of hell. i would ask you to send help but i know that to
travel in or out of this space is not possible. i am outside of time. i
cannot die. i must see what i can see and know what i know for all
eternity and less than an eyeblink at once. i know the fate of ponykind; i know the true face of civilisation; but i will not burden
you with this forbidden knowledge

your faithful student,

i... i have forgotten my name

Imipolex G

In that situation, how would you actually send someone a letter?