Well my story is different... We split up because the arguing arising from me trying to fight my corner over his general neglect (going away for weeks at a time on cheating sprees and not answering phone etc) and pathological lying, but I was so manipulated ( I suppose?) by him, I begged for him back. At first.
He was 10 years older than me and it was my first relationship, incredibly intense. He love bombed me within days.
Then just after we separated I found out he'd cheated on me with literally countless girls during the 18+ months we'd been in this deep relationship, including my flatmate, random people from the internet, anything that moved, and even a young girl where it seemed consent was unclear. He was unstoppable. He also had shallow effect and no real emotions.
I'm saying this because abuse and control is not always physical like many of the stories here. And yet I was so emotionally controlled by him, I convinced myself he was ILL and needed my help to get better.. and so I should beg for him back! I was such an idiot. I was a desperate girl. And he keeps finding desperate girls.
I saw recently online he'd shacked up with another girl the age I was when we met (19/20) - meaning he's 20y older than his current girlfriend. Such a sick bastard. I wish I could save her.
This was all about 13 years ago. I'm now married and have been in a happy relationship for 10y but I think about this traumatic experience every week, I regret to admit sometimes every day. It's like what they say about heroin - you can't match the highs, nor the lows. It's still so painful.
I should probably get counselling but I sort of begrudge having to spend money on what he did to me when I'm making a success of my life (and he's a waster / fuck up).
If I could give advice to anyone in a relationship with a narcissist it would be RUN RUN RUN and the pain you feel now is NOTHING to what you will endure by staying. Break the pain barrier and please release yourself. They ONLY get worse. They CANNOT be fixed.