Daniel, hypersexuality, impulsivity, poor judgement...those are the symptoms that got my diagnosis of bipolar 1 (4 moodswings, 2 manic, 2 depressed in one year too!) I was so impulsive and the sex drive so strong I even bought a ticket to another country to see the man I'd been talking to who was 20 years younger than myself but I was caught before I could go.
I completely understand, and you're right, no one who has never been in the throes of a manic hypersexual episode can realize how strong it is and how it can completely take over your mind. My personal thought is because sex is so hardwired into our brains and bodies that it is even harder to overcome primal urge than say an urge to buy 3 cars in one day.
For me, a major manic episode requires massive mood stabilizer and antipsychotic med doses, the good news is once I have been stable for a while I am able to go back to maintenance meds. I would suggest if you are feeling the mania and the urges, go see your dr and do what it takes to bring yourself back down. you owe it to yourself so you won't do something that makes you feel horrible when you do come back down and to your wife as well. please take care