I used to fly a very large eccentric freight aircraft called the Short Belfast. The seals around the ramp (especially) were notorious for leaking. The loadmaster used to set off on a route march around the various orifices after take-off with a tray full of wet paper towels.
This piece of aviation folklore seems to have been lost in the sands of modern time. I can remember showing a 727 crew how to get rid of this awful noise not so many years ago.
Tell your wife that she cannot get harmed by this piece of first aid. The soggy paper towel gets sucked into the leaking seal area and not her! On arrival at destination, the (now dry) paper towel will simply fall on to the ramp!
There is absolutely no way that your wife can be harmed by a leaking door seal (apart from her hearing). Compared to the tiny pin-hole leak on a seal the discharge valves on the airframe are absolutely enormous.
Pressurisation of an aircraft is actually controlled by the outflow of air from the aircraft (via the discharge valves) and not by the inflow of air from the engines. If you ask your wife to ask the captain on her next flight to show her the size of the discharge valves then she will never be worried again about a leaking door seal.
Knowledge is a wonderful thing.
Personally, I hope it doesn't put her off flying and I hope that she really gets into aviation and everything that makes it work.