Note that all of the above is true only if she is a 'good' witness.
If she is a 'bad' witness (IE, 'two faced', 'leading double life', etc.), on the other hand, you have a WHOLE nother can of worms.
Specifically, she is used to lying. TO EVERBODY. Her parents, her friends, EVERYONE, and if she's still considered a JW, she's so good at lying she doesn't even realize when she's doing it. She, in fact, completely believes the lies and can't control them - she'll lie to anyone instinctively.
Sound extreme?
Well, yeah, but it's true. Consider the JW stance on dating, as answered above. No sex. No dating outside religion. No dating of ANY kind unless you plan on marrying the person. And, if you DO marry the person, no 'kinky' sex. Lusting after your spouse is a sin. etc
Life as a JW is a very special kind of hell that will destroy your mind ('good JWs'), or cause you to detach from reality ('bad JWs').
In either situation, you don't want to be involved.
Best (only) bet is to try and get her out. If that doesn't work, forget about it. You'll be miserable.