How do you face a breakup ?

I’m 22 and I’ve been with my girl for over a year now, we had great times together and in the beginning it was wonderful but now a days, it’s bit the same, up forth and honest and yes selfish, I’m just not feeling it anymore, there’s no spark anymore, I’ve asked around and it’s obviously better to pull the pluck now, she seemed to be toxic a lot more often, gets mad when I’m with friends or family, do something that’s for me, anything not involving her she gets upset, she tells me I’m the reason she wants to live but in my opinion it’s selfish, u can’t live on your own u shouldn’t be in a relationship period, her dad isn’t around which obviously puts me as the safe haven, it’s like her world is rapped around me, but I can’t be in a relationship I’m no longer feeling, she will hate me for it, there’s gonna be tears, I know there’s no real or right way to do it but I just want to know, what’s the best way to go through with it