Recently retired husband is driving me nuts!?

My husband,Adam, retired from the military in August after 25 years in the Military.Now he is driving me batty by being around the house so much!His pension is more than enough to pay all our bills,since our house and cars are paid off.We have one daughter,who recently graduated college and lives on her own now.I work from home doing medical billing and he is always underfoot!I told him he needs to find atleast a part time job,but he's not going for it.At 44 he told me that he might not ever work another paying job again.He does volunteer at the USO a few times a week,but he has taken to rebuilding old junk cars.In the army he was in charge of the motorcade,so he knows his way around a car.Since August he has totally overhauled and refurbished 3 antique cars,and from those he made more money,even after expenses,than I make all year.So I can't really say he's not bringing any money home. I just am getting a bit irriated by not having my time alone anymore.How can I get used to this?