Planning your meals around sales helps a lot, even if you don't use coupons. I didn't when I was single and often resorted to cheap frozen dinners. You save more cooking at home, of course, but I was often out and eating on the run so Banquet dinners it was.

You guys should talk about getting a membership to Costco or Sams. You can put two people on a Costco membership so you'd have to decide who would do the shopping. It will save you a bunch on paper products. With multiple adults in the household buying in bulk makes sense.