In his book, "Give and Take", Adam Grant introduces the term Otherish. He observes that those who are "selfless" and do not take care of themselves often become very worn out, and can get resentful. Also, in neglecting themselves, they may not do their jobs as well as they should and their health may not be the best.
In one of my books I also pointed out that this song I sang at church may not be accurate:
Jesus and Others and You, what a wonderful way to spell JOY,
Jesus and Others and You, in the life of each girl and each boy,
J is for Jesus for He has first place,
O is for others you meet face to face,
Y is for you in whatever you do,
so put yourself last and spell JOY.
(I'm kinda proud of myself for still having retained that in my brain for nearly 50 years.)
In my book I suggest that always putting things in that order can spell exhaustion or resentment, and not always spell joy.
Otherish means that you take care off yourself, but you are always on the lookout as to how you can add value to other people and how you can help them on their journey. It doesn't mean always saying yes, or becoming a doormat, but it means paying attention to how you can invest in the lives of other people.
Self-care is important. Being self-less is good. But I think the point in Scripture is where focus is. Our focus cannot continually be on ourselves or we will end of living pretty sad lives -- whether the focus is on how much I do for myself, or the focus is on how much I am doing for others, if the focus is on me and what I'm doing I'm missing the point.
I guess it comes to balance, something I'm not good at, but working on every day.
Try using the word Otherish in your mind for a while. I've been doing it for the last month or so when I'm tempted to use the world self-less and it reminds me to take care of me, but invest in others.