There is much to be said for taking care of one’s self first and then when you have that well secured to use your excess of caring to take care of other’s well being.
A totally self-centered worldview is all that there is for an infant and they are not developed enough to be aware that they even exist outside of their annoying and pleasurable sensations. As a child matures at some point it becomes aware that others exist as separate beings and that to some degree they too must claim rights to maintain their wellbeing. Putting one’s self first is still a reasonable worldview for an adolescent because so much of their real-world interaction is outside of their personal control. This self-centered treatment still makes sense as an operating principle for adults who are making their way in a world which requires their creating and caring for their family. The self-care they previously needed for themselves alone is now transferring to some degree over to their family which is being considered as their extended self. Those people close to them have become part of their self-concept and thus treating those dependents well and supporting their life quests is in a real sense supporting their own life.
Moving on in physical and emotional maturity there comes a time when treating yourself with respect and kindness includes not only your family, and friends, but extends to your whole world. It includes all the people of the world, and the future people too, and thus it includes caring for the whole Earth because that soon becomes one’s self.
Treating one’s self with respect and kindness eventually becomes identical with treating the whole world with respect and kindness.