The other thing to consider is... how good is she with payments and is she able to afford it?
Not being approved for a small store credit card sounds like she has a bad credit history as banks and stores would bombard me with their credit card offers before I even had a job and from what I see, this hasn't changed. If that's the case, are you able to pick up the payments in case she fails to pay you? And if that happens repeatedly, are you still planing to stay together or will that cause problems and you will end up with a bill to pay for someone else?
Not being approved for a small store credit card sounds like she has a bad credit history as banks and stores would bombard me with their credit card offers before I even had a job and from what I see, this hasn't changed.
It could be she has no credit history, although I agree, it's usually easier to get credit now than it has been in the past. I remember trying to get my first credit card a couple of decades ago. I worked for CT (in a commissioned role) and CT wouldn't give me a credit card as I didn't have enough credit history. The first credit card I got was a 'pre-approved' one from TD that didn't ask for a credit check.