"Don't sacrifice too much, because if you sacrifice too much there is nothing else you can give and nobody will care for you." - Karl Lagerfeld
If you sacrifice yourself to your own detriment, you are a hero; that is the societal norm. However, the problem is that when you sacrifice yourself without any self-care you deplete yourself and you end up needing others to come to your rescue, by which time they will be used to you sacrificing yourself and now that you need help they will not accept the change. This is why, when people wake up to their own selves, and they start filling their own cup and setting up boundaries, they are seen as strange and selfish. Whereas the fact is that by fully practicing self-care they can then give by the order of magnitude with their full power and passion.
From our own points of view, it is always easier to help others than ourselves, there is immediate internal and external gratification. However, practicing self-care takes work and we usually suffer initial, and in some cases, sustained, backlashes from our existing tribes.
Self-care is a holistic practice where you tend to the needs of your:
Physical body - nutrition, exercise, hydration, sleep, etc.
Mental body - perspective, awareness, emotions, sleep, etc.
Spiritual body - purpose, connection, understanding, etc.
Energy body - energy hygiene, meditation, energy healing, etc.
Of course there is a balance between self-care and selfishness. If you suddenly drop all your responsibilities without any forewarning, you will have to suffer some significant consequences, that are going to make your self-care practice truly challenging. Find your balance and bring your practices on gradually and allow responsibilities to naturally release, rather than ripping them all off like a plaster. The goal is for you to become the VIP of your own life, and part of that is having the balance with self-care and supporting others.