A couple of thoughts here.
-It sounds like you didn't ask her, she volunteered an opinion.
-Her opinion wasn't all that bad. I'd have probably started repairs. Even if the money got held up, a credit card would have allowed you a 25 day grace period.
-Your opinion is also not all that bad. I can see your reasoning. You've got to be comfortable laying out that kind of money.
-When she stated her opinion, that was the time to say "I can see what you are saying but I'm really not comfortable until I see the money." That's a fair position. By not saying anything, you contributed to her misunderstanding.
So what do you do now? I'd tell her that her idea was a good one, but you are conservative with money and just weren't comfortable until you saw the money. Respect her input, explain your position.