I set up a rental for an Airbnb for two months - collected the keys on the Tuesday, moved my clothes on Friday morning and left him a letter which he got when he got home from work. I told my children - my DD15 came with me, my DS18 stayed at home.
I did this due to my previous attempts to end things resulting in him using so much emotional blackmail, literally sitting on the stairs in the middle of the house in silence for hours etc, that I caved and agreed to stay twice when I knew that wasn't what I wanted. My main trigger for ending things iniitally was him stonewalling me and DD for a month.
I had no plans beyond the end of the two months but had got some money into another bank account and a credit card in my name. After a couple of weeks of getting my head around it I looked for something more permanent and found a rental on a six month contract and we moved in just before Christmas.
It was hell to start with - constant messaging from him, him speaking to my friends and family about my mental instability, awkwardness over me getting access to money, plus the stress of having to set up a new house and being not living with my son. I met him once a few weeks after I left at his sisters house - she was being very neutral and supportive to us both but it didn't achieve anything. He took six weeks off work and basically his job in that became finding the real reason I'd left and the correct trigger to get me back. Eventually I had to tell him to stop all contact (too late really) at the end of December.
I filed for divorce in March and he was initially unco-operative but has since done the online acknowledgement, although is now ignorning my requests for us to sort the financial separation 'as we are supposed to be in the cooling off/reconciliation period'.
I've been having counselling throughout the whole thing plus taking anti-depressants and that's helped me keep my resolve but I've had to learn to set boundaries and grow a thick skin. I won't pretend it has been easy but I'm now seven months in and feel like I'm coming out of the other side. He is still on a campaign to get me back (weekly messages of family photos, song lyrics etc) but I can now let them wash over me and have so much more self-esteem.
Not once has he ever acknowledged my right to leave or that my feelings might be valid, but I've given up seeking that validation now. I spent too long thinking I needed to bring him around to my way of thinking and doubting myself, feeling cruel but actually everything he's done since has driven even more of a wedge between us. Before I left it was mostly because I no longer loved him and death by a thousand cuts, but what he's said and done since I can never come back from.
Good luck!