The Selfish Reflexive Pronouns
Det bryr sig om sig självt - It cares about itself.
Du bryr dig om dig själv - You care about yourself.
Han bryr sig om sig själv - He cares about himself.
Ni bryr er om er själva - You care about yourselves.
Vi bryr oss om oss själva - We care about ourselves.
De bryr sig om sig själva - They care about themselves.
Is that the idea or am I totally wrong?
Very close! The first one should be självt, since anything det is explicitly an ett-word.
The other two would be "Vem tar hand om oss?" in Swedish.
ta hand om - take care of
Who do you care about? = "Vem bryr du dig om?" (or "Vem bryr ni er om?" if you = you all)
Yes, I suppose so, but I can't think of uses where you wouldn't use it reflexively.
Who cares for us should be accepted. Yes, it could in one sense mean "providing care services", but it is also commonly used to mean "who cares about our well-being".