When you commit a mistake and hurt someone who is very close to your heart, then you should feel it and express your apologies. You can use a sorry letter to do so as it will be an imprint of your repentance which will remain forever with the recipient.
Here is a sample letter to husband:
Prime Line Residency,
14th May, 2010
Though we never expressed ourselves like this before and few words really don’t have any meaning in our life but today I want to express my feelings and today I want to say sorry for my obnoxious behavior. I gave a deep thought to all the incidents that have happened in the past and I realize that it was not only you but even I was also responsible for messing up the things.
As a wife it was my responsibility to be with you at every step of life and to understand your situations. No matter what the others were saying but I should support you without any question but instead of doing so I questioned you about your every action and I did not believe you. Sweetheart I know that I hurt you like anything but believe me it was not me but it was my insecurity who forcefully driven me to this situation. Although sorry is just a word but today it is the entire expression of my feelings.
I am not only writing sorry to you but the pain that I am deeply feeling is the pain that I have given you with my bad attitude. I need one chance to prove myself and to revitalize our relation. I know it is hard for you to forgive me but if you can feel my apology then I can hope to have it.
I am waiting for you to come and cuddle me with your warm love because then only I will be sure that my sorry in accepted by you.
With all my love,