Please pray for your spouse, Job2007. She needs it. She really needs it.
Yes, she does. She’s probably petrified. The OP states:
- He was fine with contraception (I’m assuming condoms?) until 3 years ago, and his wife feels like he’s “changed the rules” aka pulled the rug out from under her.
- She has MS - and 3 kids already here.
Isn’t it possible that she is terrified of what another pregnancy might do to her body? MS is a
serious disease. It’s incurable. It’s a life sentence. She could feel fine today and be paralysed tomorrow. She may feel that another pregnancy could result in her death and leave their children motherless.
If she is sick, and taking medication, why would she want to add something with as many bad side effects as the pill to the mix? Of course she would prefer condoms. And now her spouse - who vowed to love her in sickness and in health - wants to “repudiate” her in sickness, when she is likely feeling vulnerable and unsure of the future.
Yes, NFP would be the best option. If he doesn’t want to use condoms he shouldn’t. But to demand “payment” of the “marital debt” (oh so mutally loving and uplifting and life-confirming, those terms - I’m surprised your wives aren’t swooning at your feet

is the wrong way to go about it.
But she’s not there yet and you can’t force it on her. Maybe instead of looking for permission to put aside his wife and mother of his children , the OP should practice a little corporeal work of mercy and take care of the sick - body and mind. She’s lived her whole life thinking ABC was okay, hasn’t had the same spiritual revelation as her husband, her body is not her own any more with the MS and can’t be trusted or counted on. Don’t underestimate that feeling - even though it may be illogical - when it comes to NFP. Of course she would rather put her trust in a piece of latex than a body that’s falling apart on the inside and doing all sorts of things it’s not supposed to! She would have to be a robot to think otherwise, especially if her husband suddenly changed his beliefs and expects her to as well.
What was your tactic from the beginning, Job? Have you lovingly told her you believe this is wrong, and hope she will learn to see it the same way, but that you will love her and be there for her until death (which is probably weighing quite heavily on her mind now) no matter what - or did you make a pronouncement that this is the way it’s going to be from now on, innundate her with religious experts who back you up, and expect her to fall in line?
Your conversion of heart wasn’t hers. She may have one yet but only if she is truly made to feel that you care about her physical and mental wellbeing and aren’t going to abandon her and the life you made together because of something you suddenly discovered in the CCC. It isn’t her fault you didn’t know the rules when you started and it isn’t her fault she has MS and is now facing a future of incredible pain and disability, possibly alone.
I will pray for your wife, and for you.