Ashamed of or from?

[Tom]

Dear all

If I make a damaging allegation on you and after a month it is proven wrong/ disapproved, then what would I say to you as an apology?

1- I am terribly ashamed ----------you.
( from, for , before)

Or there is some better substitution?

Ever Yours

Tom

[Yankee]

Hi Tom

As part of an apology I'd say:
"I'm terribly ashamed of myself."

Amy

[Tom]

Dear Amy

Keeping the given situation in mind, could we add

for you in your sentence.?

Tom

[Yankee]

No, Tom, I wouldn't.

I might say:
"I'm terribly ashamed of myself for doing that to you."

And, just to clarify:

"I'm ashamed of you" would mean that the person you're talking to did something shameful.

Amy