Do you want unity in your marriage? Do you want her to feel safe to be utterly vulnerable and literally naked before you? Then it is NOT helpful for her to know your past sex life.
You probably have forgotten plenty of your past, but once you've told her it will stay with her for years--even decades.
Whatever sexual sin you've had before (or even the porn you've done while) is sin. It's your job as a man to discipline your mind, and your actions to be faithful to her. But if you're making her your "accountability partner" it's like saying: "honey, I'm trying not to look at other women, imagine them naked and pretend having sex with them". That will hurt her. Get your act together sir, get to a church, get vulnerable with someone--don't do this in isolation but don't load your dirty laundry on her. Because this will make it HARDER for her to make love (and of course that's what would actually HELP you avoid the temptations anyway).
So, whether you think you're just "being honest" you do not need to be unwise with your words. Words start forest fires. I speak to women daily about how unloved and ugly they feel because their husband struggles with porn. Women have constant insecurities all around sex. Your job as a man? Gratitude for EVERYTHING she is and does around sex. Tell her and show her how extremely grateful and gratifying her sexuality is to you.
And recognize you don't and shouldn't be a victim to your sexual cravings. And I am working with men to change these dynamics in their marriages and have already had incredible results:
-Women are now initiating "I can't remember the last time".
-"We made love 2 times this week and it was 'making love' not just duty sex".
-A man separated from his wife shared that they've now had several sexual encounters.
SO! If you want to know next steps with me, if you're a man, I'm opening my Clarity Calls now to you. You can book one here: www.dym.as.me This is a $500 value and I'm not sure how much longer I'll be doing these, so I encourage you to book very soon.