I don't think anyone but you can say if it's a good idea or not. Each person here has a different sitch and our spouses react differently. I did apologize to my husband. I actually met with him to let him know he was right about some of the things he said about me. I told him that I did a lot of soul searching and what I saw was not pretty. I apologized for some things I said to him over the years and for how I could have been a better person. And I let him know that now that I have had this revelation about myself, I intend to become a better person and I will NEVER go back to being that person again.
It felt good for me to tell him all of that. However, he really didn't believe much of what I had to say. He said it all sounded too good to be true, and then I heard the MLC phrase of "too little, too late". Over the months he has actually used what I had to say against me. Every time I don't react to something the way he wants me to, he says "See? You haven't changed at all....you're still the same old person you always were." The truth is I am not that person anymore and I think he actually does see changes in me. On one occasion when h was acting decent towards me he told me he had seen many changes in me, but he wasn't sure if I was capable of making them permanent. I told him no one knows that until the day they die!
So, even though my h has used my apology to attack me, I don't regret it. I felt it was the adult thing to do and it also showed him he was not the only one in the marriage who had made mistakes. We both have. I actually told him that even though blindsiding me and leaving me the way he did, it was the best thing he could have ever done for me. Yeah, it still hurts, but I would have never made the changes in my life I needed to make if I hadn't been dealt a blow like that. Not all of what my h has said or accused me of is true or has actually happened, but the hard truth is some of it was. And that's very humbling to admit when you realize you are guilty as charged.
The evening that I told my husband this, he kept shooting back at me with different things like do you remember when you did this? what about the way you talked to me when this happened?, etc. And you should have seen the look on his face the many times when I said, "yeah, you're right. I was wrong. I should have never treated you that way and I'm asking you to forgive me." One time he said "well, you think you're always right". I said, "well that was the old me.....now I know I'm not always right. I'm wrong a whole lot of times!"
I wish you well if you decide to apologize to him. But, please be aware he might not react like you want him to. And do your best to not get sucked into any negative talk. Be humble, sincere, and then end it.