OP, first off how horriffic for you...both in the event and in your subsequent treatment by the FA. Did you happen to get the FA's name? Because I would definitely be mentioning that in my complaint.
Redtailshark gave some excellent advice.
Speaking for myself I honestly don't know how I would have reacted in the same circumstances. Sometimes when things like this happen, things so far out of what you expect, you draw a blank.
That said, I'm really good with coming up with a response AFTER the fact, when it won't do me any good. But I'm ready if there's a next time.
In redtailshark's excellent post they wrote:
I suggest to you and all female travelers that they rehearse what they will do under these circumstances - i.e. know what your point of legal contact will be at the airport, how the national police at your destination will handle these type of complaints, and immediately make them aware of what happened.
OP, I know that you're dreading your return flight, and while it's highly unlikely that something like this will happen again you can now plan out what you will do IF it does.