@turningpoint  
Oh, I’m just tackling the supernatural obstacles. If you’re worried about getting past her friends, then you have all of Ponyville to deal with.

@FanOfMostEverything  
and Spike

@FanOfMostEverything  
They are 5 more things in your way dude

First, you have to depress her, to negate the cartoon character invulnerability.
 
Second, you’ll need to sever her then-weakened link to the Element of Laughter, which is going to be even harder now that it’s back in the Tree of Harmony and has the local analogue of Yggdrasil reinforcing it.
 
At some point, you’ll have to destroy Boneless. It’s a potent artifact of laughter magic in its own right, and may act as a substitute Element under the right circumstances, which probably include a Bearer on death’s door.
 
Then and only then do you have a chance of killing Pinkie. You’ve also left Equestria vulnerable to all kinds of eldritch abominations and whatever sealed evil has yet to breach its can. I hope you’re proud of yourself.

is impossible, give up