You may be panicking slightly but you're right to identify potential issues with this.
My lovely ex pil almost divorced when he retired because he was driving mil bonkers! Went from working 8-10 hour days to being literally at her feet all bloody day she couldn't even go Drs alone! They are the most laid back, loving couple but honestly he was lucky there was no patio!! 😂😂
Eventually she blew up at him and told him he needed to back off, he was all hurt at first and it was looking a bit precarious then his sister told mil "build him a shed and get him a hobby" she'd been through same with her husband. He now happily spends hours building "experiments" a la Wallace & grommit, occasionally he'll come up with something useful.
Keep him busy and feeling useful. He can do all the online shopping, budgets, meal planning, family calendar administration, switching all your bills to cheapest option, helping any kids/grandkids with homework, even some gardening stuff sorting seedlings etc
Fun stuff - mn? Reddit, Netflix, reading, puzzles, computer games, jigsaws, crafts (doesn't have to be knitting/sewing/crochet though I know men that do there's also felting, rug making etc)
www.instructables.com/id/Manly-Crafts-1/
Bookbinding, whittling etc
Who in your circle is around when you're at work that maybe can keep him company (if he wants)? Cheerful, practical, upbeat types preferably.
Also probably obvious but he needs to watch his diet, not only to avoid too much weight gain but to make sure he's getting good nutrition to aid recovery, focus on protein, calcium and fibre (sudden reduction in mobility can also slow the bowel, plus depending what meds he's on they could have constipation as side effect. I'd recommend getting a gentle laxative in just in case)
You might find he's tired for longer than you're expecting too, sleep = healing so if he beats himself up over having naps etc remind him of that.
Also even before he can weight bear there are still some exercises he can do and that not only aids physical health but mental too.
Watch for pressure areas developing, he's not just not weight bearing on his leg he WILL be weight bearing instead elsewhere and fear of pain can make patients reluctant to shift positions as often as they should.
Use the aids you're given/recommended like grabbers and pull rails, the last thing you need is either of you incurring injuries from trying to manage heroically when there's no need.
Good luck with it all.