Well, my wife has two of the same problems that I think you may have.
1. Women in general seem to be more attached to their current locations than men are. They seem to dislike change for whatever reason, and are afraid of leaving their comfort zones. My guess would be because women are more social, and enjoy knowing the people around them? I don't know why, I just know of 3 women in technology, and all of them feel the same way (reluctant to leave a job)
2. Don't worry about what they think if you decide not to take the job. I also think this is a women thing, as women tend to be more empathetic, and worry about what others will think. They can give you $10,000 more, and all you need to say is "I've decided not to take this position". Make up your mind before you talk to them, and make sure to consider all of the possible outcomes first. Think about what if they offer no increase, offer a bonus, offer more than $5000 extra, etc. Decide what your reaction will be, which may even include "I will need to think about this, I will give you a call tomorrow".
Good luck in either case