Dear Mr. Brown,
Thank you very much for your kindness in asking us to attend your opening ceremony, but I regret very much that I will not be able to go there as I already have an important previous engagement that day.
I send our congratulations and best wishes to you and will be together with you in spirit on this happy event.
It is a pity not to have your company in my opening ceremony.
I meant to take this chance to get together with you; we have seen each other for about a year. I also want to thank you for your supporting in my hard times. I can achieve nothing without you, not to say owning a company of my own. I have been looking forward to enjoying this happy moment with you.
Anyhow, I understand you; you always keep your promise. That is why I appreciate you.
I am sorry to hear that you will not be able to attend my opening ceremony.
Thank you for your congratulations and your best wishes. I will send a video tape to you so that you can witness the scene as if you were there.
Best wishes for you.