I did try.
He had an affair and he really wanted to leave me and the children and be with her, but she ended it and went back to her previous partner. I certainly wanted to separate, but circumstances went against it and he asked me to try again. I couldn't really discuss it with anyone in RL as everyone knew us both and I thought knowing might change their attitude and behaviour toward him. I was lost really - had Mumsnet been around then, things ... my life ... might have been very different.
After a few weeks, the situation morphed into it being my fault and I was bewildered when he started setting conditions and allocating blame. I was rubbish in bed, I was too fat, I didn't take enough (any) exercise. (I did have a stressful job and was the main breadwinner). We stayed together for a further 8 years during which time I always felt second best and that a part of him had never returned.
After 8 years he said he had had enough and left - even orchestrating our separation to suit him, involving us living together for a further year because of DC's exams and during that time meeting someone else online and visiting them abroad twice (using our joint account for air tickets). We had been married for 23 years by the time he left. If he had gone 8 years previously, perhaps I might have had a chance to start again with someone else - but I was beaten into submission by the time he left.
After he left I found letters showing that within 3 months of him begging for a second chance, he had been in touch with the OW again asking for another chance with her, which she refused.
I did try.