Only a fool would think that the checkout girl asking you how you are today really cares for a meaningful response. We reply to such phatic speech with the appropriate "Good thanks" even though we may have just had open heart surgery.
There are degrees of care. The first degree is the parent for the child. They really care. The second is the care of a partner for their loved one ( of the moment). The third is everyone else. And when we split from our relationship the aforementioned partners go to the third degree. Their and our position is tenuous at best.
Now I know there is a lot of noise about how much people care for us. But when it really comes down to the divine level of care it is really close to our own personal ego as to how much we care. My mother had a saying: " Blood is thicker than water". It answers how we feel when it comes to care. Most everything we say to others in terms of inquiry as to their personal well being is what is called phatic speech. We do it to stay polite. Isn't that an eye opener?