Mine has said "I'm sorry" a number of times. When he saw how shocked & devastated I was at BD he said it over & over until I just told him to stop. He has said it a handful of times, usually when we've hugged during rare interactions. Once it was "I'm sorry I did this to you".
My take on this is that it has all been to soothe his own guilt. I do think he has regretted what happened, but has been so compelled/addicted to following this course of action (the infidelity, the abandonment, now the D) that he hasn't accepted any accountability for his actions. He doesn't really blame me; I've even gotten "It's not you, it's me", but he hasn't accepted his wrong-doing either. He has been overheard explaining that "Things just happened". RCR has a good rebuttal for that in her articles, LOL.
I understand the sickness here & have love & compassion for him, but I don't believe he has apologized to me. He does not have remorse; he isn't making amends on any level. Forgiveness is a process. If he returns with sincere actions, it will come more easily. If our lives diverge long term, I think forgiveness will eventually come, more by default than anything else.
Detach and Survive: A Book of Self-Care for the Wives of Midlife Crisis Men
The Journey from Abandonment to Healing, Susan Anderson
Healing the Shame that Binds You, John Bradshaw
The Addictive Personality, Craig Nakken
https://www.midlifecrisismarriageadvocate.com/chapter-contents.htmlM'ed 41 years
BD-Jan 2013
Legally separated Feb 2013
D'ed without my consent July 2015
H M'ed OW Sept 2015