I sympathise. In the job I'm on maternity leave from I have a colleague that I have no supervisory responsibility for at all, thank goodness for that as our boss had no idea how to deal with her either. She thinks she's very computer literate, and she may have more knowledge of Excel than your colleague, but she chooses not to use any of the work I've done, and won't let me show her anything. She reformats documents prepared using my precedents and her work looks awful (and what a waste of time).
It's not about training or age in such cases though, I know lots of people even older than my colleague (early 50s) who are much more up for learning new things, for heaven's sake even our former line manager tries harder, and he's a solicitor and manager, with more than enough on his plate, not a secretary! (Management responsibilities have changed recently, so all secretaries come under the admin manager).
Is the document one she has to amend or merely to read? The latter - could you just give her a print. If the former, ask someone who isn't you to create a shortcut and show her how to use it. My suggestion for it to be someone who isn't you is based on just that, it avoids you having to deal with it yourself, and maybe if she resents you she won't resent someone else in the same way.
Does she resent you as her manager because you're younger, newer etc? I started 6 months after my colleague (back in 1998!) and I'm perhaps 15 years younger, but worked for the senior solicitor (2 different people) except when he had to change that arrangement because of her behaviour. And was once told I was considered the "senior secretary" although we never had such differentiation officially.