If the photos are hers she can do with them as she likes - she owns the 'copyright'.
However, I can fully see your point and wouldn't like it myself. I think all you can do is ask her to remove them - she isn't breaking any criminal law, nor is there anything in civil law to help you.
As you say, you'd end up arguing if you asked her to do that, but I think the fall out would be much bigger with a solicitor involved. You could try contacting AIM but the photos don't breach their guidelines - they are not offensive in any way.
This is something that is going to cause a lot of problems for a lot of people, I think