why do you need to get stuff that lasts a long time? if you live in a city of any size, grocery stores should be near enough that shopping once a week shouldn't be a hardship. Many fresh things will last a week, and the ones that won't can be eaten at the start of the week. Just don't buy more than you'll eat, and EAT LEFTOVERS.
As well as leftovers, vegetables, fruit, cheese, nuts and bread are all instant. might be more expensive than ramen but you won't feel like crap all the time either. Freeze the other half of your sliced bread or bagels, it comes apart easily and when toasted tastes exactly the same (untoasted tends to be soggy unfortunately).
but I must admit, ramen+a crapload of frozen veggies (at least the same volume as the noodles) is my guilty insta-meal of choice. Cooks in <5 minutes including time to boil the water, which is most of the time needed - and I always have both stored. Not all that healthy though, despite the veggies.