Acc is dead on with this. TJT, you could have done everything right and still ended up here. There is no guarantee of long-term wedded bliss in this life! So many factors play into these things, it is impossible to know what would be different if you were different. Maybe he would have hated having someone that always agreed with him! (Believe it or not that is a fairly common complaint. "He/She never had their own opinions."
While I am an advocate of assessing what you could do better, the balance is to not fall into the trap Acc is discussing. 180ing on bad behavior (in my sitch I had a lot, things like being controlling, being overly critical, etc) is essential, but beating yourself up and making yourself believe that "if only I hadn't done this, we'd still be happy" is counter-productive.
Marriage is 50-50. Own your 50%, but do not take the blame for his 50%.
M(53), W(54),D(19) M-23, T-25 Bomb Drop - Dec.23, 2017 Ring and Piecing since March 2018