You know I don't shoot as much as I used to. To be honest if I need a gun for home defense I think I would prefer my 20g. I am more comfortable with it. Plus the intimidation factor of a shotgun blast I think helps ward off any accomplices
Get out there and practice with your handgun. The 1911 has the easiest manual of arms of any pistol out there. If you shoot 50 rounds a month, you will at least be keeping up your knowledge of the handgun.
I try and shoot my Glock at least that much, and as I live in the country, I can shoot off the back porch.
Another point is, you can get practice ammo relatively cheap from places like Wal Mart and Dicks Sporting Goods. Almost every Sunday Dicks has some sort of a sale on handgun ammunition. You don't have to have hollow point ammo to punch holes in paper targets. Full metal jacket ammo is just fine for that purpose.
Optimally, I might consider the purchase of 500 rounds from some place online like Georgia Ammo, or www.aimspurplus.com
If some SHTF situation happened, I would think 500 rounds of 40 cal ammo in the closet would be a calming thing. Especially if there are reports of looting, like in New Orleans.
Shooting a handgun is fun. You should do it as much as possible.