Why do I stay at work when I could go home?

You already know this. You aren't staying late because the job demands it. You stay because you're good at it, and at home you feel unsure, maybe even unwanted. That's the truth under the excuse. Don't flatter yourself with the word 'ambition.' Ambition would leave once the work was done. This is smaller: you prefer the room where you win. That isn't virtue. It's comfort wearing virtue's clothes. You can't control whether home is easy. You can control what time you leave, what you do in the first ten minutes there, and whether you keep lying to yourself about why you stayed. If things at home feel heavier than tiredness — real conflict, real distance — talk to someone outside this page who knows the whole situation.