Fiction portrays very little in a realistic light. Just look up articles about how much characters would really make and what lifestyle they would have in the real world.
Ironically I'm usually less concerned about the physical expectations than the emotional ones. I've seen a lot of marriage break ups in friends and family and they all seem to come down to the idea that such a relationship is there for you and what you want out of it. When that person starts wanting things too that the other side doesn't want, suddenly the relationship is worth nothing because the other side isn't a person, but exists purely as maid, breadwinner, sexual partner, emotional support, ego stroker completely devoted to you, etc. Both genders have this. For every big breasted harem lead, there's a shoujo manga where a hot guy sees the best person in the world in some plain girl with no domestic skills.
It why, while I like some of those types of shows for the comedy, there are lot of anime couples I don't see making it past their first fight.