I work better alone. Having someone else there, even if they aren't purposefully distracting me, just adds another tiny bit of awareness: Is he hungry? Is he bored? Does he want coffee? We haven't had lunch - should I cook? I should tidy. I feel like when there's a guest in my house I need to take care of them somehow, and make the place (and myself) presentable. When I'm by myself I can just focus on work, forget to eat for a day, and not bother cleaning my house and nobody will give a crap.
Even when I know he is totally fine fasting all day with me if that's what it takes while we focus, I still get concerned with starving the poor guy while I'm in "the zone". And often he cooks for us as well, which is nice and very appreciated, but then I'm distracted by eating and then thinking about how I should return the favor that evening by preparing dinner. But what if I was going to work through the evening?! You get the idea... I much prefer to be selfishly alone and not think about anyone else's presence.
But my boyfriend seems to be the opposite, and closer to what you're describing. He sometimes likes coming over specifically to work. He says my focus on work during the day helps him focus and stop procrastinating, too. In the end, we compromise. I find a way to still be productive and focus when he's here, and accept that I'll just feel a little bit bad about not paying attention to my visitor.