I can't say I agree with what you're saying here. My wife constantly denies me sex, my ex-fiance did and my ex-wife did. When I do occasionally get to fuck her its with a condom, as it was with my ex's. Trust me, its no lie. None of them enjoyed penetrative sex with me and i'm ok with that, we are very happy otherwise. I masturbate quite a lot and all were ok with that, encouraged it and my current wife has even bought me fake pussies/fleashlights as gifts.
She bought me a set of custom embroidered 'wankerchiefs' for my 50th birthday because she'd prefer I release any sexual tension I have by myself. Would I like to fuck more often, absolutely, but I do cum with in a minute or so and its never a timed, planned orgasm, it just comes upon me from nowhere, so its sometimes like a ruined orgasm, as in, there is no build up, crescendo etc. wheres as with masturbation, I can edge for ages and have total control over it until i'm ready to squirt. So for me pulling myself is a better orgasm for me. I wish it wasn't, but it is.
Plus i'm very sexually submissive, so have no skill or ability to initiate sex, I get it only when its given. So if my wife isn't horny for me, then she doesn't start the wheel turning. At best, if she is horny, she'll have me lick her to an orgasm or two, then if she's still in the mood, she'll let me penetrate her a cum, the condom is so she doesn't have to deal with my mess, afterwards or the next day. Occasionally if its on a Friday or Saturday night with no work the next day, she might let me take the condom off, which I sometimes will, but usually I just leave it on as its reduces the guilt I feel later when she has get up to clean her pussy even though she got no pleasure from me.