You can think of -hood as species or kind or group or order or class, and -ship as state.
Neighborhood (the group of your neighbors)
Knighthood (membership in the group or order of knights)
Friendship (a state of amity)
Hardship (a state of difficulty or suffering )
Womanhood (the class of women or membership therein)
Statehood (the group of recognized political entities or membership therein)
I should get extra points for defining a -hood with a -ship and for confusing you with statehood :)