Minaone, others have chimed in here, but I wanted to give you a man's perspective. 
I've been faithful to my wife since we began dating when I was 22 years old. That was back in 1993, but I can assure you that young people were quite sexually active back then. It wasn't halcyon days and virginal chaste dating with chaperones. This was the same year Pulp Fiction came out in theaters. 
Anyway, I never strayed, never flirted with another woman, never developed anything that could have been described as an emotional affair (unless you count a brief texting flirtation with another woman 3 years after my WW's affair and after my WW had failed a polygraph). 
All that to say: I never felt this was a burden for me. I was married to a beautiful woman, I loved her, I was attracted to her, we had great sex. I'm also a good looking man with a good physique, money, and a good career. I'm not rocking a dad bod, so it's not as if I would be unable to talk another woman into the sack if I wanted to.
I didn't feel the need to seek out other women for sex or anything else. Men get sexual thoughts and urges all day, every day. The number is very high, and I can attest it remains very high for a man in his 50s. 
And? So? By this logic, I suppose men could say they just have to act out those urges with as many women as possible. Would any human system -- small tribe or larger society -- work at all if this were the case? No, of course not. 
Your husband is being a bullshitter.
He's also, frankly, a terrible father. No good man, no good father, would shit all over his family the way your husband has. He's acting like a 13 year old boy who just discovered masturbation. It's the reasoning and behavior of a boy.
It's really actually offensive as a man to hear another man talk this way, even, or especially, a young man. He needs to buck up, grow up, and stop trying to lay his shitty irresponsible choices at the feet of his gonads. 
Are any of your children girls? Can your husband honestly say with a straight face he would want your daughter(s) to be treated the way he is treating you, or the way he treats the other women he seeks out for a quick lay? 
There's not something engrained in men that makes a man seek out another woman outside of his marriage (in fact, if anything, science suggest monogamy is the NORM in human functioning, not some social construct forced on us). 
There's nothing you've done to make your husband this way. 
It's all on him as an individual. 
Period. 
Full stop. 
Now, you're also dealing with a sexual addict and a serial cheater. Really bad combination. Serial cheaters are notoriously difficult to reconcile with. You need to know that.
Couples counseling usually only works before infidelity takes place -- or only after a wayward spouse has spent a lot of time working on themselves. Otherwise, a couples counseling scenario is likely to devolve into a push to make you rugsweep or take the blame for your husband's shitty behavior onto your shoulders. 
Don't do that.
 [This message edited by Thumos at 10:28 PM, Tuesday, January 18th]