I had a similar thing with my small dog and realised that when she eats the tag on her collar knocks on her bowl and makes a noise that puts her off, although that doesn't sound likely with your dog as this is recent behaviour.
I have had to hand feed my dog in the past because she was very ill and it was the only way I could get her to eat.
In order to cure this behaviour I started putting a small amount of food into her bowl at a time - she's fed on wet food. If I put it all in at once she either eats it too quickly and vomits or she just can't seem to cope with all the food at once. Now she's happy to eat out of the bowl if I feed her gradually.
What sort of bowl are you using. Some dogs don't like metal bowls I've heard, as they can see 'another' dog's face in them while they're eating. Some small dogs are happier with a flatter, plate type, bowl.
She might just find dry food a bit boring, as Glitter, say try mixing it with some wet maybe.
Have you had her teeth checked out. If she's six she might have some tooth issues.
Oh and one last idea. Are you giving her lots of teats and things in between meal? If you are it could be she's just not hungry when it comes to meal times.