Guiltyprty1 - I know exactly what you are struggling with and going through.
I only recently gave a proper full disclosure after lying and TT my poor BS for over 2 years. I have brought hell into our lives that she didn't ask for or deserve.
I have been with my BS for over half my life - 21 years ago ago this month was our first date. I had 3 PAs during two of her pregnancies and was addicted to sex chatting with dozens of women as well as porn. I lied and betrayed her trust and love in every possible way and live every day not knowing if I will ever get a chance to get it back.
Only until I stopped letting the fear and blind faith dominate my choice to be selfish could I let go of what I had done and hidden. I wish I had done it before. I wish I had done it on my own without ultimatums and her forcing me. This did horrible damage I may never be able to recover from.
But I love her and she deserves everything in the end. I can't keep living my life as a sell out hiding from the past and not dealing with it. It is hell but it is getting easier and I do feel different having the truth out in the open. My BS doesn't believe it is everything and yours probable won't either. You can't control what he accepts or believes just as I can't control what my BS believes. My lies and TT have decided that for her.
Just don't stop or turn back. Do it for him. But realize also that you are doing it for you. It will help you.