The information that we have concerning our existence is something we have thanks to scientific investigation and intellectual application, not the result of religious belief which, in the christian sense as in most others of that nature, tended to provide "answers" to that question before any data had even been assembled.

"Beyond astronomical", whether the pun is intended or not, is not an amount. It is simply a figure of speech that indicates the speaker has encountered a numeric value beyond their imagination's ability to appreciate in terms of quantifying. That this undefined amount can then be deemed a criterion by which a miracle can be declared depends therefore completely on how willing the speaker is to believe in the miraculous. Rubbish, in other words, since the conclusion has been reached even after they have admitted that the available data has not been read by them, let alone understood.

"Naturalism", if it means a refusal to accept answers that do not have demonstrable rationale in their deduction, is the antithesis to faith. Contrary to the speaker's assertion this approach has yielded, thus far, the only answers we have that we can trust. Blind faith on the other hand, if it had never been informed (often against its holders' will) by the results of scientific deduction, would never have arrived at anything even approaching as credible and trustworthy an answer to life's origin as an understanding of physics, biology and evolution has given us.

Subjectively of course we can all choose to accept or reject any answers we we are told apply, but in adopting certain answers as being the only correct ones we must expect to be taken to task over them and explain our choices rationally. Scientifically deduced answers can be thus explained. Faith-based answers are unequal to this very simple test and the rest of the quoted passages from your husband's relations bear this out. Her repeated assertion that she "doesn't have enough faith to be an atheist" is, given her exposed ignorance of the subject matters that she herself raises, simply a synonym for the fact she does not have the inclination or ability to read, learn and assess the available data before arriving at a conclusion.

Her mind is made up and in a manner that precludes normal debate. Unless she entertains the possibility of this being true no meaningful debate, let alone a conversion to rational thinking, is likely.