My first thought--you have been a nurse for more than 20 years according to your post--so your children are not small and can take care of themselves. Second thought, your husband is in the NYPD, you both have chosen jobs that protect and care for those who cannot care for themselves, and jobs that require you to be at work during emergency situations. Did your husband have the same dilemma? Did he ask you if he should stay with "the children" so you could go into work? Likely not--he went in because he knew he had to serve the people, those who need help. As a nurse, you have the same obligation. Many hospitals provide day care in emergency situations, and most nurses have contingency plans, family, friends or a day care center that can take small children who need supervision during times when both parents have to do their jobs.
If you don't want to have to be responsible to give care during an emergency, then I would suggest you look for work in another setting. You can work in an MD office, Case management for an insurance company, as an industry clinical support, or other position that does not require work in a hospital or long term care facility. I am a nurse, but have chosen to no longer work in a hospital for many reasons. There are plenty of options for nurses who do not want to be on "disaster duty" for whatever reason.
But if you do work in a hospital that has a policy to call people in when disaster strikes, then you have chosen to accept that duty and responsibility, just like your husband did when he signed on to the NYPD