Would you prefer the word paralyzed?
Actually, that would solve half the problem.
The word “hostage” implies that she is being held back from doing something, and also that it is someone else who is holding her back.
Neither of those are true to any extent at all, so it is twice wrong.
The word “paralyzed” implies she is held back from doing something, but does not imply it is being imposed on her by someone else. So it is only wrong once. Which is twice as good.
If you want a word which is accurate, you might say “while she is on some other boy’s list”. The word “is” captures the meaning you are (should be) trying to convey perfectly.