looking for a manga

im pretty sure this was part of an anthology? it was a sci-fi manga, this guy is up in space alone and he gets regular video calls from his coworker (maybe boss? idk) down on earth. up in space with him is some sort of ai or robot who can change it's appearance. the ai looks like his coworker, and he has sex with the ai regularly. he plans to confess or smth when he gets back to earth. he counts down the days, but on the last day its revealed earth was destroyed a while ago, and all the messages he had been receiving from the guy were recorded a long time ago, and there is no earth or coworker for him to go back to. i cried really hard but i dont think i saved it and its been bugging me for a while. can anyone help?