Honestly, not too much.

If it is something she is truly passionate about, then if she quit, she may still be very resentful.

I can sit here and say "her bad", she shouldn't have cheated then. But nonetheless, if she is as passionate as she says about being a volunteer fighter, she will be resentful.

I'm just being real. If it really is a dealbreaker for you though, you need to be honest. I'm not judging that. Like I said, resentment is a marriage killer. If your resent her for keeping the job, and she resents you for making her leave the job, it's going to be a problem.

Say she quits the FD. What is the next thing she does that isn't acceptable that she needs to give up?

Before you have her do it, you need to really really sit down and have your boundaries straight because if she keeps doing things and you don't like them and want her to give them up as you go along, it will be controlling resentment.

Truth is, if she wants to have an A, she'll have an A. At the firehouse, at her fulltime job, with the gardener...

she si giving you full transparency. I can't say anything for sure. No one can say anything for sure. Right now, she doesn't seem to want an A.