It's just a stunt to boost publicity.
Marvel comics killed Steve Rogers (Captain America)
DC comics killed Bruce Wayne (Batman)
Guess what ... Both are on the way back this year. My thinking is that Archie comics will drag this out for a year or so, and then things will get called off on the wedding day. Not an Archie reader, but it makes sense.
EDIT to add: I've talked to friends who read the Archie books, and they've told me told me it's not a stunt, and that Betty will end up with Jughead ... I'm still thinking the Wedding will get called off