@DankyWanky420 If you break the fences shortly after placing them, you will get them back (so that you if you mess up placement, you can re-arrange). This was added early in the game as a convenience feature for players so they could re-arrange their fences when initially placing them
@Negative_9175 when NPC's are below 10 hearts (or if you are married to them), their friendship level will very slowly decay if you don't interact with them