Losing my faith in the human condition

I'm trying to figure out what exactly is the relationship for people.  What do they do for each other.  I just don't understand it.  Do parents need there children more than there children need them or is the relationship animalistic all together and as soon as they can "hunt" they should be allowed to fend for themselves.  In dating relationships is there more than the comfort of a warm body at night.   I just feel like I'm losing faith in people it sucks