In regards to a letter to creditor or creditors, it is hard to be objective and realize that the worst responsibility in the world is for creditors to deal with nonpaying customers. And to be perfectly honest, usually a letter to creditor or creditors is not ever sent. Most nonpaying customers are struggling financially and emotionally by the time the creditor letters of past due bills begin to arrive, sent to customers who pretend the letters are not there.
If a letter to creditor is sent immediately, informing them what is going on and why the bill has not been paid, usually they are fair and pretty decent about it, willing to work out payments. Otherwise, they become frustrated to the point the bill is sold to another debt collector who is more ruthless with even higher interest rates, and so on.