Welcome to the forum!
As has been suggested, her weight may not be too little after all...with the obvious conflict between what you feel is "correct" and what others (with, it seems, lots of cat experience") believe what may be "correct, I'd also suggest you check with your Vet....I'm willing to bet that, for a simple weight check, you might not even be charged! But, if she hasn't yet been to the Vet, this might give you another reason to go.
What you're hearing about wet food is absolutely accurate....I'll go further, dry food really isn't fit for a cat! What's worse is what most dry foods are made from....wheat, corn and other grainy ingredients. Cats, by nature, need meat, and...those who don't get it end up with many of the nasty illnesses and conditions that you can read about on this forum.
If you want to learn what a cat needs to eat (and, only if you want to invest a little time into that) check out what this cat Veterinarian and nutritionist has to say
Originally Posted by .rae.
...i've tried to switch brands, but it didn't work. another thing, wet food is much more expensive than the dry one. i can't afford it for a long time.
One thing about "switching" foods...it cannot safely be done "instantly"...when we
say "switch/change", we understand that to mean slowly transition
to the new food, adding increasing amounts of the new to the old over a period of a week to ten days. Otherwise, you risk the chsance of gastro problems (and more Vet bills!).
Now, about the cost part
of all this...the thing is this: you can pay a little more now for wet food - OR - you can end up paying a huge lot more in Vet bills, treating the illnesses/conditions that your "cheaper" dry food has brought on....your choice.