No matter how well you think you know someone, they can still be putting up a facade without you realizing it. (I mean this as a general statement; I’m not trying to cast doubt on your relationship with the Chassidishe couples whom you know.)
Anyway, even if those couples are really happy (and I hope they are) that doesn’t account for the entire Chassidishe community. I highly doubt that every single Chassidishe couple in the world is happily married.