The variable here is what does she (and the rest of your old friends) have to gain by coming to your 21st etc? At the end of the day it's just another party. If they want to go to that extent to come, they must have really shit lives. So it can't be just for the party - you must have some other value that they, or she, would like.
At the end of the day your mindset is wrong. The choice should not be - should i cut off my old friends or should i show them my new self.
Instead, it should be, this is who i am, and these are my beliefs. Would them coming fit in with that, and would I like them to come? If so, then go for it!
No one can bully you mate. There's nothing wrong with having them over. If they come, and they are pissing you off, just kick them the fuck out! It's your party, it's your house.
There is literally no need to give a shit about people who piss you off in life. There is an abundance of amazing people in the world. I have so many amazing friends, anyone who gives me the slightest bit of shit I just totally cut them out of my life. There'll be someone ten times as good as them to take their place. And this is why I only have positive people and positive feelings surrounding me.
You choose your reality. If you don't like it, change it
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