Serait-il possible de me corriger mon expression en anglais

Sujet du devoir

Nous devons écrire une lettre à Madame Jobs afin de lui montrer notre reconnaissance envers son mari, à propos de ce qu'il a fait.. J'aurais aimé que vous me corrigiez mes fautes d'orthographe, expression, grammaire..
Merci par avance.

Où j'en suis dans mon devoir

Dear Madam Jobs,

I am writing to tell you about your husband. It was an extraordinary man. He has created the Mac, I pod, I phone, I pad and many others technolgy. You don't know, how am I grateful.When I knew that Sir Jobs had died, you don't know, how I cried. Today, I think about all I can do, and I am very disappointed because now the products will be not the same than before. What would be I, if he did not have was there ! I think I could not speak, share photos, videos with my friends, my family in USA, Australia and in many others country. It will be a disaster. My life will be so sad ! Hope it is good well for this terrible trial

I promes you, I will go to see your husband, because it is important for me and I think that it is for you too.

Yours truly

John Brent