Your job is not a ‘make-work’, it is important and sustains your sense of self-worth.
During the time he was ‘away’, you took on more work to fill empty hours and avoid going to the mausoleum which used to be the matrimonial home.
You will not stop taking on more work, will not rush home, leaping out of staff meetings, or tossing a file in the pending tray because you have to make dinner.
You feel no guilt telling the kids to go to friend’s house after school, you’ll bring a pizza, that’s how you got through the days/weeks/months of his adultery.
Now that he is back, he can find his own food, or starve.