By "do so little for you" it really means someone who doesn't meet emotional needs you have deep down inside, reciprocate your love or service, or let you know you are deeply cared for - NOT by our society's means either (i.e. material things) but doing it in the way YOU genuinely respond to.... I have love to give regardless of my well being....Period
Yes, some people really do suck. Why invite them into YOUR precious life? God gives us a finite number of days above ground. Why pollute a single second/minute/hour/day/year with a sucky person? If they were the tray that raw chicken comes in, how long could you stand to leave it in your kitchen trash? Time to kick those stinky peeps to the curb trash can for pick up, baby!