I have a suggestion. Make space for chastity to be about something other than sex.
Buy a cheap medal device that fits well. Practice wearing it for a few hours at a time so you know it won't cause too much pain.
Put it on Friday. Then prepare a candle lit massage for your wife with chocolate covered strawberries. Then tell her you have a big confession to make, that you have been bad. Show her the device and tell her could not help yourself, you wanted to try chastity to see how it feels. She will probably be relieved you are a perv (which she already knew) and not confessing to something worse.
So announce that you will be wearing the device all weekend. And you will be holding the key, keeping safe and clean, and she doesn't have to do anything.
Tell her that you have been wearing it for "sometime", ask her when the last time you had sex is ( or she saw you naked). Just don't tell her how long, just say "you didn't notice? Don't worry about it sweety".
Then announce, "I am wearing this until Monday morning. The problem is the device is making me insatiable, I can't get your sexy body out of my mind. It's driving me a little crazy!! But I can't have sex or orgasm!! So I want to give you a full body massage tonight. Do you want lotion or coco butter?"
Basically you need to impart that you are going to see it through. And that you will be channeling the sexual energy into non-sexual things out of desperate desire for wife.
Then do those things - breakfast in bed, clean, take the kids, special snacks, laundry, foot rubs each night. You should know what she likes. Make the entire weekend about her and not about sex, as if you are treating her to your first Valentine's Day together.
She doesn't like oral, so don't even go there. Don't touch her sexually unless she asks for it. Snuggle and kiss her for hours if she wants. Ignore the hammer on your pants, and you will make her comfortable with chastity.
Right now she thinks the chastity is a weird thing for you. Own the weird and make it about her. But don't ask, just do it.