Yes, it definitely is possible for HPV to lie dormant all those years--in you or your husband or both--and now pop up with an abnormal
papPap smear
Pap smears and cervical cancer smear. In couples like you, it is not unreasonable to be concerned about the other possibility, i.e. more recent infidelity on the part of one partner or the other. But it need not happen and you need to judge your husband's fidelity based on what he says and/or other evidence, not on the basis of your HPV infection.
Best wishes-- HHH, MD