“Because they are so sentimental.” “But I like sentimental people.” “Never marry at all, Dorian. Men marry because they are tired; women, because they are curious: both are disappointed.”
Marriage is not seen as a deep bond but rather an inconvenience or a meaningless vow. It's sort of like a ticket one needs to punch or purchase to stay at a certain level of society, but nothing more. Real love is said to be outside the realm of a vow like marriage, but this makes it seem unattainable and almost unreal. Lord Henry’s brash statements about Genius and women cut down Dorian’s joy and show a very simplified view of the world.
