Barb, I'm sure you are just snapping at each other because of the nicotine withdrawl. Quitting smoking could make a saint cranky! Also, many people who have heart attacks or heart surgery go through a period of depression and/or anger. It's normal. It's not easy to live with, but it is normal.
Take the money you are not spending on cigarettes to buy lots of heart healty fruits and veggies. Scour the internet for recipes to try out. You never know. You two might find out heart healthy is not so bad.
Take care of each other and best of luck on the new lifestyle.