My version of this lasted seven years. He was a sort of my boss I am freelance and he basically had control over my career. I looked up to him, fell in love with him, and we had an intense relationship over this time, that was largely secret and never became sexual although it was highly emotional and time consuming. It was utter madness. I could not extricate myself because I was dependent on him for my career. He led me on terribly, destroyed my peace of mind, made me behave in ways I am ashamed of, but on the other side, developed my career and was in a strange way my closest friend. I tried to manage the relationship with therapy, spent thousands on it but as I could not break the relationship and could not change it, it was a waste. It HAD to end, it was horribly toxic, but I was powerless to do it. In the end, he engineered a situation that was a kind of public showdown from which neither of us could return. Like you OP I have never known such pain. It was a madness. I am not recovered. I broke my contract to get away from the situation complicated by the fact that almost all of my friends were connected to my line of work and I have had to withdraw from them too because it is unbearable to talk about, as well as professionally damaging. But eight months on I am getting there. Here are things I did, good and bad.
No contact. But I did, and still do sometimes look at his whatsapp activity. Just to see him 'online' gave me a bolt of comfort when I was lonely.
Wrote him letters which I didn't send.
Wrote about him endlessly in journals, trying to make sense of it.
Talked about it to a very few friends, who all said it was an abusive relationship and I had done the right thing.
Let people into my life. I realised he had sucked up my entire emotional life for years. I didn't really know who I was. My life is richer now, though more painful.
Listened to Peter Walker's CPTSD audio book. Life changer. Also other books on trauma bonding and CPTSD.
Considered myself very ill. Treated myself accordingly. I was extremely tired for a long time. Still am not 100%.
I still miss him every single day. But I know it's based more on pain than love so I don't give in. But I don't deny myself the thought that one day I might.
He hasn't tried to contact me, which helps! I think we both realised we had to stay away from each other. The ending was so very devastating, I almost take comfort from it. There is no way to be in touch without a long time passing.
Sorry OP, this is a long response. But maybe it helps to see first how long these things can drag on, how dominating they can be, and how hard they are to recover from. I am doing well these days, but I still consider it early days. Good luck.