Thanks for your query. Based on the facts that you have posted it appears that your husband may be more than 65 years old.as he has undergone prostate surgery
12 years ago.
It is not uncommon to have decreased libido and not getting hard erection at this age.What you are thinking as a erectile dysfunction
may be retrograde ejaculation
which is common after Prostate surgery .
He can take phosphodiesterase inhibitors (Sildenafil
)after consulting your family Physician .He will guide you about the dosage and timing to be taken and will issue prescription of the drugs.