How possible is it for a woman in a monogamous marriage for 45 years to be diagnosed with cervical cancer? Is it for instance possible but unlikely?

Definitely possible! I'm sorry this diagnosis has you concerned. This is neither your "fault" nor is it likely related to anything from your husband. Cervical cancer can occur on its own and need imply nothing else! best wishes !
Cervical Cancer. I am very sorry to hear of this and wish i knew more to give you the best advice. It very well may be that your cancer is not related to hpv, the common reason for cervical cancers in the world. It is also possible that you or your spouse were exposed to hpv, if that is the cause of your cancer, through skin to skin contact and not through sexual contact. I hope your doctors are helping you.
Yes it is possible. About 20% of cervical cancers are not related to the hpv virus so it is possible for a woman in a monogamous relationship to get cervical cancer.