The trifle may be a very short keeper depending on the fruit used in it as some fruits deteoriate quicker than others, even in a jelly. If the fruits are canned, then the cream and custard are the things to go off first. If the fruit is fresh, well ...
Fruit cakes, pound cakes, sponges all freeze well as well as the other items mentioned. If you have all these things to use up, my suggestion would be to freeze everything that you aren't going to be able to eat within say four days. The trifle would need to be one of those items. Everything else can then be eaten at will.
Personally, I tend to use my senses, if it doesn't smell bad or look bad but I am still dubious, I just do a bit of a taste test. I use expiry dates only as a guide as they are only useful for average storage and transport conditions - at best. Sunday nights I can be found intimately peering at items in my fridge ready for the rubbish collection on Monday mornings.
Too many restaurants, not enough time...