And most likely, those things went missing for her long ago, leading to her not being interested in sex anymore. Sounds like the sex is just a symptom. If she's checked out of the marriage, you probably played some part in that. Aside from the fact that women get bored with the same ole, same ole sex (and it kills their libido), women have to feel emotionally safe and seen before they are interested in sex with a long term partner.

Get yourselves to couples therapy to talk about the health of your relationship more generally. Once that's strong and vibrant again, then see if the sex thing still needs addressing. Chances are, if the rest is working better, so will that part. Men use sex to create intimacy; women need that intimacy to already be there before they are interested in sex with a long term partner.