Well don't be paranoid, way more people survive. Usually the people who die are very old and didn't have the medicine they needed stock piled. Or they live directly on the coast, think they are superhuman and get swept out to sea, house and all, once the surge retreats.
If your wife is within a few miles of the water, she definitely should evacuate. At least to a friend or family member house a few more miles inland.
Other than that, if you can communicate with her, make sure she has water. If bottled water is hard to come by now, she can fill the bathtub and all sinks. Gross but potentially a life saver.
Neighbors tend to come together and pool resources and support. Even neighbors who don't like each other if you have that scenario.
Cell phone towers could be down for awhile, internet too, so if you don't hear from her, don't freak. Plus the network is super bogged down when towers come back up.
Preparation is mostly for comfort, unless you are old or otherwise in poor health.