I suggest that you do not buy a handgun first. Instead, attend a training course. Most instructors are enthusiasts and will have a variety of guns available. Take your wife too because she needs to learn gun safety and self-defense techniques.
skidmark's comment of "The best advice there is for chosing a handgun is to find out what "feels right" for you" is well intentioned, but erroneous, advice. The reason it is not correct is because you have no idea what features you need in a defensive handgun. NRA Basic Pistol is a good start, but will not help you very much with regard to the features you need in a defensive handgun. Attend a two day course. Jay Cunningham runs courses out at Beaver Valley Rifle and Pistol Club in Pennsylvania. Look around for similar courses (check the syllabus) in your area if that is too far away. You will have a much better idea of what will and will not work for you at the end of the training. This will be an evolution; what you think works for you now will change in several years, especially if you continue training.
I can tell you that it took me several years, many rounds fired, and at least three courses to settle on what I really like. For example, take the
Browning Hi-Power MK III. It's a nice gun and the 9x19mm version carries very well. It shoots well and is very reliable. The magazines are well made and withstand use. But, the gun needs tons of work out of the box. A fourteen pound trigger pull is unacceptable (yes, I took one to class with the trigger like that). The edges are very, very sharp and I sliced open all the fingers on my support hand multiple times. The magazine well needs beveling to facilitate reloads; I had to figure out the trick to getting the magazine quickly into the well during the course. All those modifications require cash and the gun must be refinished after the work. There are so many guns on the market today that require minimal work out of the box that I just moved on.
Do not be lulled into the notion that revolvers are "simple and easy"; the operational manipulations can get quite complex. Revolvers require quite a bit of training to learn to operate at speed. Semi-automatics are easier to shoot and operate. This does not make the revolver ineffective defensive tool. You will need to spend extra time perfecting your trigger control. Reloads are more complex and require diligent practice. Remember, I am talking about operating a revolver in a defensive situation
at speed, not on the square range shooting for tiny groups.
Do not fall for the "grip angle" and "feels good in the hand" arguments. They are not really relevant unless the grip angle causes some sort of physical problem from recoil or the grip. What you think is a good feel may actually not be what you need for managing recoil during rapid fire. Some say grip angle is necessary for creating a "natural point". One would think one needs that for aiming the gun,
but it's absolutely not true. There are many ways to shoot and are generally divided into "aimed fire" and "point shooting". Aimed fire uses the sights, which is a method to overcome the natural point of the gun. Point shooting is all about figuring out what horizontal means and developing confidence in your point shooting at different distances. Both styles have their place and require the shooter to learn the gun. You will never shoot well if you fail to develop proper trigger control and do not learn the gun you are shooting. There is no substitute for practice and the number of posts you have on a forum does not count.
I'll use myself as an example. SIG P-Series pistols point perfectly for me. They tend to point right on target. 1911's point low if they have a flat mainspring housing and point just a little low with an arched mainspring housing. S&W revolvers are about right, but the Ruger GP100 is a tad off with the grips installed on the gun. Glocks point very high for me. Yet, somehow, I can shoot every one of these guns well using aimed or point shooting. I even do the vast majority of my shooting through Glocks. The reason is that I know all these platforms. I know how all of them will shoot and I know how to use sights. I focus my practice upon mastering trigger control. Sights are sights; they all work the same (except for red dots, but I'm excluding those from the discussion.). Triggers, however, are all over the place. If you can master trigger control, you will do very well with just about any pistol. You'll still have to learn the other skills such as recoil management, reloading and so forth.