Whether we compromise in the relationship, take care of others or suppress our own needs, in essence, we are trying to take care of ourselves in the way we can. To have self-care requires the ability to be intelligent. In popular language, it is necessary to have a relatively healthy "stomach" to digest these things.
The process that adults can Self Care is a process that a child needs to learn to separate from his mother. By accepting and completing the separation process, this person will realize that "I need to be responsible for myself". Only after having such an understanding can he go on to learn self-care.
Source: @beinked21