Hi seatrout and welcome to JWD. Hope we can help you here.
Please don't be offended, but you would not have been seen as a "potential convert". You would have been seen as someone who was interested only because you had your eye on one of the "sisters". You would have been thought of as a "worldly boy" who could corrupt this clean and moral witness.
This is a quote from a Watchtower article which may help you see how JWs view dating someone who shows interest but is not yet a JW (1 Nov 89, "Do Not Yoke Yourselves with Unbelievers"):
18 WhatifyouareattractedtosomeonewhoisstudyingtheBibleandattendingthemeetings,althoughheorsheisnotyetbaptized? We rejoice when anyone shows an interest in Bible truth. The question, though, is: Should you pursue your inclination? Frankly, the course of wisdom is to wait until some time after your friend is baptized and is making progress in displaying the fruits of God’s spirit before you date. (Galatians 5:22, 23) It may not be easy to apply such advice, but by doing so you will demonstrate devotion to Bible principles; this will lay a fine foundation for true happiness in marriage. If your friend genuinely cares for you and is truly coming to love Jehovah, no doubt he (or she) will be willing to wait until both of you are "in the Lord"—dedicated and baptized—before courting.
You would have to be a dedicated and baptized JW, attending 5 meetings a week and going from house to house approx 10 hours per month before she would even be able to think about courting you. PLEASE DO NOT PURSUE THIS PATH.
Even if you were a potential convert at the time, she would not have been disciplined. She may have been counselled for being friendly to you but seeing she overcame this successfully by rejecting you, she would then have been upheld as a good example.
Any strange behaviour on her part would have been because she was trying to hide her friendship with you from her family (severely frowned upon).
penny2