While I didn't have a severe break like that (just the coracoid process, which healed without surgery), my separation was about the same.
I thought I'd never regain flexibility in my right shoulder. For almost five months I was pretty much left handed. I figured if I got stopped by the police I'd be in trouble because I wouldn't be able to put my hands overhead, behind my head or behind my back.
But around mid-September, almost five months after the injury, it began improving. Now I have about 95% of the original range of motion. In the military parade rest position I can't quite match my right arm to my left. Ditto, hands behind the head. But I have almost full range of motion with little discomfort, although I need to warm up slowly before riding my bike or doing any serious exercises.
There's still a bit of a knobby lump and gap at the acromioclavicular joint, which the ortho docs say will be permanent. It aches every day, mostly in the middle of the night and morning, but eases after I'm up and moving around, and there's little pain when I'm exercising -- which is great. Just riding my bike or indoor trainer and getting the blood and brain chemicals flowing is a great analgesic and anti-anxiety treatment. But it can be a bit depressing to fall asleep feeling great and wake a few hours later with the same old aching again.
Anyway, with encouragement your wife's recovery should go well. It can be frustrating after awhile because it seems to take several weeks to feel any improvement. But in my case the shoulder felt better quickly after I noticed the first improvements a little over four months after the injury.
I think what I missed most wasn't being able to brush my teeth, comb my hair, putter in the kitchen, etc. -- all the stuff I was accustomed to doing right-handed. It was not being able to sleep on my right side. For months I had to prop myself up with pillows to prevent myself from rolling over onto the bad shoulder in my sleep -- that was excruciating. But by September I noticed I'd waked up a few times on my right shoulder and it was only a bit achy and stiff, but not agonizing pain. I still need to arrange a few pillows just right, including propping up my right hand and forearm with a thin pillow. But I usually fall asleep on my right side now -- the pressure on the shoulder actually feels good.
And I do a little stretching all day. Not full PT sessions, but at least once an hour I'll do a full range of motion and stretching. Only takes a minute or two. We probably should all do that anyway. But it's essential now.
And it's motivated me to improve my bike fit. I'd been accustomed to poor posture, hunching my shoulders and neck. But now I'm making lots of little adjustments when I find myself trying to force my body to fit the bike rather than the other way 'round.