I don’t know without a doubt that our culture became so insistently unhealthy when it comes to the idea of self-care with the advent of differing variations of Christianity becoming the “state religions” of the assorted European nations. But, there is — consistently — a certain amount of misunderstanding about it in our culture today.
I wouldn’t blame it on the Bible or on the base doctrines of Christianity (those that are universal among all flavors of Christianity). No, I would place the blame firmly on the shoulders of humans and their interpretation of those basic doctrines.
If you look at the Bible, charity and compassion for those less fortunate as well as love for your neighbors (regardless of who they worship or what they do, because the Bible states to be compassionate even to those who hate you. Proverbs 25:21- => If your enemy is hungry, give him food to eat; if he is thirsty, give him water to drink. In doing this, you will heap burning coals on his head, and the Lord will reward you.) is the choice you must make if you wish to do your best to follow in the footsteps of Christ.
But, the Bible also talks about sacrifice and about martyrdom.