I actually do have a dremel but I'm worried that I'll hurt her or file them too far?
It's actually much easier not to take too much off with a Dremel than it is with clippers. When you use a Dremel you're literally doing the tiniest of touches at a time and as long as you do that you can see when the texture of the nail changes (which means you're getting close to the blood supply) and stop before you hit it. With clippers, even super sharp ones, there's a limit to how small an amount you can take off in one go so, especially if you're trying to get the quick to recede, it's very easy to take a little too much off and end up going too far.
It can be very challenging to get nails to the ideal of not being able to hear them tapping on the floor, it's quite dependent on the shape of the dog's foot how easily it can be managed. I aim for that short but as long as the nails are well clear of the ground when they're standing square on a flat, hard surface I'm happy.
Just to give you an idea with one of my dogs, these photos are from this afternoon and show how DWhippet3's foot looks when the nails have just been done. In the standing photo you can there's definite clearance between the nails and the surface which allows his toes to be in the correct position. However these do still tap when he moves on hard surfaces so ideally they'd be a bit shorter.
This blog post (and the video included in it) is an excellent starting point for getting nails sorted.
This is a guide to cutting black nails with clippers and this one covers Dremelling black nails.
This YouTube playlist has loads of really helpful videos on nail trimming covering everything from technique to desensitising your dog to the tools you want to use to options like scratch boards to allow dogs to self trim. The latter can be really helpful to use whilst you're getting your dog used to the Dremel, it's surprising how much of a difference a quick go with a scratch board can make.