Hello! I happen to be Vegan and suffer from vaginismus. However, I do not have anemia. I do suffer from Pelvic Floor Dysfunction, which plays a roll in my vaginismus(In addition to me having extreme anxiety as well).
Also, meat can be known to lower sexdrive and take a toll on overall health, so I highly doubt in any way that is causing her vaginismus.
Make sure she’s eating tons of veggies which are rich in iron, as well as getting her B12. Nutritional yeast is great for that! Hope this has helped!