I wasn't teasing.
I asked OP a question, and clearly said I was just curious. I see lots of things which don't always add to the discussion. If OP chose not to answer, or even return to the thread, that's okay.
But others jumping in and saying something not only mentioned but emphasized in the initial post isn't relevant, going off on tangents, and further directing me not to ask OP about it? Odd.
But, moving on....................
The point I think other posters are trying to make is that while the fact the co-worker is older is relevant, her specific age isn't. Whether the co-worker is 35, 42, 47, or 58, so long as she is older than the OP, the OP feels compelled to respect her as an "elder".
OP, I do think this is an issue you should take to your manager. This is absolutely an issue a manager should address. (Quick aside, from working in HR I know managers can often get upset when employees bypass them and go to us - especially if the issue isn't really under HRs jurisdiction.)
In your case, your co-worker has filed a formal complaint with HR. Let me also say that from my experience the only "formal" anythings are usually write ups done by managers and signed off on by the employee. If HR didn't talk to you
which is the utmost basic tactic for an investigation, then it's safe to say they didn't take it seriously. I'm sure I've had a number of employees approach me in my career with what they thought were "formal" complaints, but was just me listening to them and saying, "This is an issue for you to resolve with your manager and your co-worker."