Just to give a somewhat different perspective of 'after care needs'. I've had two OHS within four years. Both times (the last being 14 months ago), I was able to walk up full flight of stairs immediately home from the five days I was in the hospital the second time. (I was in longer the first time as it was emergent and I was on a balloon pump for 4 days before I was well enough to undergo surgery.)
I showered, washed my hair, dressed, made light lunches and prepared/warmed easy dinners for me and my husband. I was able to load the dishwasher. I certainly tired easily and required afternoon naps, but took daily walks outside in March weather in New England. My DH was wonderfully supportive and ready to help me in all ways needed but for the most part, I was okay on my own. Sure, he changed sheets on the bed, took me grocery shopping the first few weeks and carried the bags etc My second surgery, my cardio gave me the okay to drive at just about 3 weeks post op. That's quite early.
My only point is that it is good to keep in mind we are all different. Some are able to be far more independent faster than others. It is not always a correlation between age or even physical fitness going into the surgery though most of us agree the most fit you can be Usually it will lead to an easier recovery but no guarantee.
I was diligent in following the 'do not lift more than 10 pound' rule. It can do you harm for the rest of your life if you do not allow your sternum the best possible healing.
Plan to have some help when you are first home but you may be pleasantly surprised to find after a day or two you will be fine on your own during the day.
All that being said, IMO it is a full year to completely heal and for some, they say it has taken longer.