Expat,
I think a couple needs to be friends, for a rich, lasting marriage. And I agree, marriage needs a degree of passion. But some couples get used to each other; they take their spouse for granted. And there are guys who refuse to take the blame for anything, even when they know they're at fault. That must be a guy thing. I, personally, am happy 'n content; though I gripe about gender personality differences. All that comes under the category of being human. Two people spending day-in, day-out in one house, are bound to get on the each others nerves, now and again.
But IMO couples can and do have long marriages, without the red hot passion dancer describes. Two people can co-exist with a compatible, content love affair and live happy, healthy lives.
IMO