Little. Blue. Pill.
I'm not a nympho (that's an actual classification of an obsessive compulsive disorder or addiction)... However, for 9 years I enthusiastically had sex every day (barring illness, etc.). Sometimes 2-3x per day.
I have a High sex drive. I'm a very physical person. Always have been.
I've been celibate for 2 years now come aug. HATE it, but it was/is my choice. First, because I lost all respect for my husband, now because I don't date and have no plans to for several years (divorce). My STBXH happily had sex every day, but when I closed the muffin shop, he was like yours. He'd initiate maybe once a month. Fortunately for me, since that was the last thing I wanted... ER... With him. I never cheated, I keep my promises, but my sex drive remained (and, sigh, remains) the same. Some people just have Hugh libidos. Some don't. And a LOT of people have medical or depression issues.
Viagra has become such a staple, that men who would never, ever, EVER talk about their sex life with anyone, much less their doctor, WILL see their doctor for those little blue pills. AS WELL it's the side door to getting checked out (blood pressure, hormones, cancers, etc.). Sometimes they'll check before Rx'ing, but if it doesn't "work"... They'll definitely check.