Declining an Offer

[LAS22]

I have officially made my decision on which grad school to attend! Accepting was easy, but now I officially have to decline another offer-- a moment I have been dreading. I really liked the other program and the work of the faculty member is outstanding. This was honestly the most difficult decision of my entire life, and I almost feel the need to voice that to her.

Does anyone have any advice on how to structure an email to a faculty member declining their offer? I am a bad judge on when I've said "too much" or "too little" and I feel like my emails always turn out sounding strange, awkward, or rude. I would appreciate some examples of phrases you all have used in your experiences! Thank you!