I'm sorry to read about your flock. I don't have any advice in regards to security, but there is already some great tips being shared here.
I'd like to share with you whats recently been going on here with my flock though.
I lost 16 birds over a 2 week span. About half to illness, 1/4 to hawks, and 1/4 to raccoons. I took a complete crash course in "What happened to my birds?!" It was very difficult for me to handle. None of my chickens actually give me eggs or provide meat, their just pets. I love them with full on emotional attachment. My first death was my favorite Serama by a hawk just 2 feet in front of me. It put me in tears, and my wife was the one counseling me. Then my flock got smaller
by the day from there. (including 4 of 5 guinea fowl too)
I think you should get more chickens. It might not be the right time, I'd work on the security aspect, but I encourage you to get more chicken. They are just wonderful to have, and amazing stress relief, dogs with feathers, and if you get the right chickens (something I have a problem with) they feed you too.
I don't know why you keep chickens, but with your wife so bothered from it, I would guess it's not to just throw them in the frying pan. I'd also guess you know how awesome they can be. Find ways to adapt, research not only proper security, but the predators themselves. Ask tons of questions here at BYC. The amount of experienced advice here is astonishing, and the people are too! What's good for the goose might not be good for the gander, but the crew here has tons of backgrounds, budgets, locations, and experience levels to draw from.
For me, most of my chickens where/are pretty small. At one time I had 19 chickens with only 2 being a large fowl breed. This is not my only problem (small easily picked off birds), but for me it is the biggest threat and easiest to address first. This is Nugget, a Serama pullet, and not my smallest chicken. You can see, they are no troubles for a hawk or raccoon to just snatch her.
I am restructuring my chicken flock. What Bantams that did not die where rehomed. I moved my Seramas inside the house (I'm not giving up on my favorite breed!). Then I researched breeds till my eyes cracked from lack of blinking. I want to know what breeds are predator savvy, what roosters will defend their flock the best, what breeds are just to big for hawks to carry away. I still haven't found a breed with night vision I could teach jujitsu to, but when I do, it'll help with the raccoons. Will my search criteria fix my problem? Maybe not, maybe so, but it's a fighting chance at least.
What I do know is I wanted to quit. I felt crushed. You can see in my thread, more than once I said "I can't handle taking lose like that", or "it just hurts to bad to deal with."
I'm still bothered by it. Izzy would cuddle up in my neck and take a nap while I'd sit and read. She would fly to and perch on me when I walked by. She was my favorite chicken, and also the first to get taken. I wholeheartedly miss her.
Still though, and I think most people here would agree, if it's something you love, you should continue to do it. Strive to make the living conditions safer. Educate yourself on the predators in your area. Get some new fluffy butts, and love them.
Our situations are not exactly the same, but I lost a lot of birds and I could have prevented almost every death. I just didn't know what to do, or what I was even doing wrong. I'm not going to quit though, and I hope you do not either.