Same here. There's plenty I've accepted blame for. I've struggled with porn for most of our marriage without getting help (that worked) and after we got turned down for a christian foster program, she just shut me out, then Covid hit and within 6 months she was writing lesbian romance, spending all her time out with "friends". I was doing my best, but had zero support from her, while also shouldering all the stress from single income, massive debt, etc etc... taking care of the kids everynight while finishing MBA.
So 3 years later, happened to come across her secret IG account she'd been hiding for now... 3 years. It was a simultaneous feeling of an anxiety attack, clarity, and relief all at once. It made not just the last 3 years clear, but the last 18. She'd never been particularly intimate physically with me, not since the honeymoon, not affectionate, and took ever chance she could to be somewhere else, usually with some female friend I didn't know. The loneliness was crushing... and yeah, at times the urge to end things was strong.
Finding out was thing that honestly gave me hope... not for us, but at least for myself. If she didn't want me, and especially if she were out messing around, then I'd be free to move on (from a Christian perspective).
I joined a support group shortly after finding out working on my issues, and when I confronted her, she was angry that it took the thought of losing her for me to change... I haven't said it to her face, but frankly it's not the thought of her leaving that scared me, but what if she didn't? Then I have to be the bad guy that tells my children's mom to leave.
She still blames me for everything, and accuses me of manipulation, all the typical deflection techniques, but it's clear now, so it doesn't affect me the way it used to.
Now I could pile all the petty things on top of this (uncleanliness, unhelpful, never helping with cooking, etc) but to have a clear, "This is why it's over" is a relief.