From your post, I understand that you might feel your writing skills are limited, but, you really don't need our help with this. You just need to write from your heart. Doctors receive letters of appreciation from their patients and the family of their patients all the time.
I don't believe they're looking at whether the grammar of the letter is correct or not, as much as they just appreciate the word of thanks for the treatment they have provided to the patient. As far as writing a 'love letter', something like that definately needs to be written by the sender. No one can express love towards another like you can.
If the woman you send the letter to loves you back, she won't care about your grammar - she'll just care that the letter is from you. If she DOES care about your grammar, you don't need her anyway. You have a good heart.
I would take that over correct grammar any day of the week. More.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.