@auntiejessi
As far as I know she doesn't read things about health stuff and internalize it. She just doesn't seem to take care of herself. I go to the doctor at least once per year, but that's a specialist. I'm going to go to a regular doctor next year, too.
Her dad died when she was in her mid-teens, I think.
I don't think she fears the doctor. I think she fears diagnoses of any type, really. I don't know.
Yes, oral cancer can be linked to HPV. It's also linked to heavy drinking and smoking.
It's also really uncommon. From the American Cancer Society:
"The American Cancer Society’s most recent estimates for oral cavity and oropharyngeal cancers in the United States for 2022 are:
About 54,000 new cases of oral cavity or oropharyngeal cancer.
About 11, 230 deaths from oral cavity or oropharyngeal cancer."
https://www.cancer.org/cancer/oral-cavity-and-oropharyngeal-cancer/about/key-statistics.html
Statistics are similar in other developed countries. Considering that there are 332 million people in the US, it's an uncommon cancer.
If you've been monogamous for that long, any HPV you had prior to your relationship is gone. If you had it, and it leads to cancer, that's already going to happen. If she is that concerned, she should make an appt with her doctor and get an exam to look for any changes.
In your situation particularly, oral sex isn't a real risk factor. If you were single or non-monogamous, I'd advise otherwise.
Is she usually a health-anxious person? Risk-averse? Has she had any abnormal pap smears? Is there anything to indicate she's had HPV?
If she's been an active and willing participant in oral sex thus far, and seemed to enjoy it, I'd suggest some therapy and an exam with her doctor.