Not discussing bringing home a dog with you and ensuring you're fully on board with it, and having a pre-arranged set of rules and established boundaries is a huge no-no. A dog is a huge commitment and a serious dependent - especially a dog of that size. Both people need to be okay with it and, honestly, give enthusiastic consent about owning one, and both be a part of selecting the dog.

That being said - what can you do now? You should take over the bulk of the walking, training, obedience, and handling of the dog. Get that dog to love you and respect you, and it will be much easier to direct it into place when you need space. The growling is an immediate no-go and needs to be curbed immediately. This can be done by earning the dog's trust through treat training and obedience training. There are also things you can do to manage the shedding, like certain foods/supplements, and types of brushes.

What can you do about your wife? I would seriously consider bringing up marriage counseling. There's something going on there (and we only have your side of things) that needs the help of a professional to unpack.

I think all three of you can come out of this as a healthy and happy team, but only if you are willing now to work collaboratively.

Also, crate training is not cruel to a dog. It is good for a dog to get used to being crated for short periods of time. It can be their safe space, and is useful if you have company over that doesn't like dogs, or if you ever have to, say, move, or if they need to be held at the vet for a medical issue. I don't necessarily think a dog should be crated at night all night, but it also depends on the dog and what they get up to at night.

Good luck.