"men are visual creatures" my arse. They can't even tell the difference between the colour pink and the colour salmon half the time!
Men oogling, watching porn, or prioritising other women/his interest in other women isn't unavoidable.
It's just a lot of men get into relationships, and even marriages, with women they're not actually all that into. They want a partner for what they can do for them (attention, sex, cooking, cleaning, life admin, sometimes status etc) so settle on the first one who fits the bill, performs the right actions, and will have him. Because a man needs a woman to do that stuff for them, because he can't rely on mummy anymore (without embarrassing himself!).
But because he's not actually all that keen on the women he's paired up with sexually or romantically, he'll have a roving eye and roving actions. And these will take priority over you, because it's a need of his. And he will say its normal, and you'll convince yourself it's normal, because whilst you know and feel the truth, it's too painful to accept. He's just not that into you, I'm afraid
Could be avoided if men were a little more picky over who they agree to be in a relationship with, learn to live without a woman and so only go for the ones they're super into... But eh.
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