Modesty, the reason that dressing modest is so hard for some women is because this yetzer hora has grown out of control in some women. Tznius becomes second nature after a bit of taiming the yetzer hora.
If a Jew has been eating treif it’s much harder for them to stop eating it than someone who has never eaten trief. But after a while of not eating trief one doesn’t have to keep themselves back from eating treif- it becomes second nature.
It’s a real shame that in some frum communities the basic mitzva of tznius has become such a big effort to keep because they have become lax in them. I think that the trying to make baalie teshuvas out of non-frum Yidden should take backstage to making sure we frum Yidden are strong in keeping basic halacha.