Friends help friends move.
Real friends help friends move bodies.
Hmmm... I have 3 classifications of friends (outside of family, 2 of my best friends are family members. I have 3 very close friends). In general, though, I'm more like your son. I give ALL of myself into relationships, so I do so sparingly.
1) Military folk. I could pick up the phone and have anywhere between 6 & 30 people on the next plane. And ditto. Facebook has been LOVELY for these friends. But even before facebook it could be 3 years since we'd last talked, and the conversation starts midstream
2) A fairly wide circle of aquaintences / people I respect / like/ love spending time with... but rarely phone up. This is where I'm like your daughter. I KNOW a lot of people, and while most of them I would consider friends*, they're not the "Call at 2am sobbing or bouncing up and down with excitement" type of people.
3) Close friends. This number just got REALLY small. Anyone whose knee-jerk reaction to finding out my husband nearly killed me and also attacked my son is to "remain neutral", or think I'm making it up (and even worse; extoll his virtues), I no longer have the time of day for. I was just gutted about this last night. Then sleep happened, and this morning I'm done. This isn't about just choosing sides in a divorce. This is choosing to be friends with someone who smashed my head into the ground and fractured my skull. Nope. Sorry. Huh-uh. Finis. I won't be friends with someone who thinks it's okay to use my head as a basketball.
3.5) Sister by another mother, best friend in the whole world. We're coming up on our 20th.