Because God directly affirms the need and blessing of communal worship and the necessity of regular communion together with believers. An impulse contrary to that, which separates the believer from the flock, wouldn’t line up with what God has already disclosed about himself and his church and worship in biblical revelation. It would be one thing if it was an extra opportunity, like a bible study or class, but the main weekly meeting? That wouldn’t pass my sniff test either, though it would certainly appeal to my flesh.
Just following on with this. God is not going to tell an individual to do something contrary to what he has already said. I've heard it said many times, in many different pulpits, "the voice in your head is not God." Some say it is Satan, some say it is our own self speaking.
Even before my husband was a pastor, we were pretty careful about our reasons for staying home from church. Tired and just don't feel like it? I always think of the early believers who had to hide out to worship because of persecution but took the risk rather than stay home. Or, for that matter, believers in some places today who have to meet in secret. People who travel great distances to go to church.
Now that doesn't mean there aren't reasons to skip church sometimes, besides sickness. But in my experience those times are pretty clear and I don't have to try to justify it in my mind.
BTW all my comments are assuming the family is in a healthy church, no scandals or other nastiness going on.