I believe Highbury is very fortunate, indeed, that there are so many happy endings in that village.

Harriet and Robert - newly married (finally!)
Emma and Mr Knightley - to be married
Jane and Frank - to be married
Mr. & Mrs. Weston - married with a new baby
Even Mr. & Mrs. Elton are happy in their way

But to get to that happy ending they had to go through some struggles:

Harriet and Robert - poor Robert had to wait for Harriet to get away from Emma and come to her senses, and poor Harriet fancied herself in love with 2 other men.
Emma and Mr Knightley - each thought the other was in love with someone else and they were going to lose each other (I hope that makes sense).
Jane and Frank - what a struggle to keep their engagement secret and deceive everyone in town. They really did almost lose each other.
Mr. & Mrs. Weston - hhhmmmm - I don't think they had any struggles, except that Frank didn't visit right away.
Mr. Elton had to find a wife elsewhere after being rejected by Emma, and Mrs. Elton had to endure poetry from puppys before meeting her man. ;-)