怎么写英文感谢信?如果一个人,在我困难的时候,借了一些钱,我应该怎么写感谢信,

Dear XXX,
Thank you so much for lending me money when i was in the most difficult times of my life.You are just like God-sent,you are simply an angel!I know how hard it was nowadays when people ask for help in monetary matter.Whenever I have enough,I will repay you as soon as I can...not only monetary gift but also my sincere thank you (from the bottom of my heart).
I will remember all the good you did to me and my family.I also want you to know how grateful I am to have a true friend like you.
Thanks again and I wish you all the best in your life ahead.
Your friend,
XXX