I feel like calling it 'depriving' them of sex is a disservice. Sex in a relationship is not everything and if it's important enough to consider cheating over then something is wrong with the person considering cheating.
While most people enjoy sex there are plenty of reasons someone might not. Past trauma/PTSD, for example. And for many women I know, myself included, knowing that there really isn't a reliable form of birth control that doesn't rely on the man that they can get without going through invasive procedures, often that they cannot afford. Condoms are cheap sure, but if the man doesn't know how to use it properly or in the event it breaks there's backups but they aren't the greatest option. For women like me who don't want to be pregnant or have kids and can't afford birth control due to it being more and more inaccessible with each passing year general abstinence from sex with masturbation to satisfy needs is something that's growing.
If my partner and I were not having sex I would be totally find with that and maybe masturbate on occasion after making it known I wanted to be satisfied in that way and having them continue to say no. In fact I'd be fine if we *never* had sex, because there are other ways to connect with someone and spend time together in a meaningful relationship.