Has he always been this way?

It sounds like he's so exhausted that he feels he needs a bit of 'cheap and easy' entertainment, and what he's doing with the computer is a great way to get it. He can switch his brain off and be entertained. This may sound stupid, but perhaps he feels as if he needs to work hard mentally to stimulate you (not just sexually). I don't know how "advanced" you guys are with the relationship, but maybe what you and he need is a weekend, or even a day, where he has absolutely no work commitments to worry about, he's well-rested, and there's no "cheap entertainment narcotics" around. If he's willing to try that, then that might be the trick. If he's able and not willing to try, then I'd be inclined to think that he's a grown child. You want a man.

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I want to know everything
I want to be everywhere
I want to fuck everyone in the world
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