This is an interesting question and I totally can empathize with you, deeply in my heart. I've had to make sacrifices with my husband. I'm a cat person. I miss having a cat and will greet every cat I see while out. But I just had to make a very hard choice...cats or my husband. I chose my husband. But I am very very happy with our bird. But as soon as the bird dies, and the husband dies, guess what I'm getting? Morbid, I know, but it's true...if things happen that way.
Yes, he should be understanding that you are grieving your bird and let you grieve without comment. I grieve for my cat and it's been five years. But maybe he just does not get it...and that's ok. He does not have to. I would give a dog love and connect with them if they were my own, but I don't like other people's dogs. Especially if they jump and lick...no thanks. I would not appriciate having to live with a dog that jumped and licked me all the time...again, I would let a cat do that!
Now the heavy part...to get a parrot or not. This is just my opinion, I would choose love. If you are not in an abusive relationship, choose love. Maybe he feels second best to your love of birds and that causes the strife? Is this the reason for his comments when your bird passed? It was not a nice or supportive thing to say and I would be so upset over that! But I wonder if he feels like he's not as important and that's what makes him dislike parrots? My husband loves our parrot, but we have had words over time not spent together because I get super focused on Emmi. I've tried hard to keep that balance.
You married him for a reason and you created a child together. If a bird is grounds for an almost divorce...that's scary. I'm the stepmom in my marriage, I could tell you the horror stories of my husband's ex and the men she chooses to be with. That's the scariest part to me. If you seperate because you want a bird that your husband does not, you lose the right of who enters your child's life. And you lose the person you love, to another...or many others.
I wish I could tell you to just get the parrot you want and bring it home...but that's just not good for a marriage. It's not fair to the parrot to live around someone who resents it, and it's not fair to the person who thinks having a parrot is a miserable life. It sounds like your husband did try and it just didn't work out.
But I deeply sympathize with you. It's not easy. I'm glad he's compromising with a hanging cage. Maybe he is understanding of your need to have a parrot in your life to make such a compromise, even if he would never want a parrot. What about building a shelf for the cage and getting a Green Cheek or Teil? I promise, you won't be disappointed with the green cheek! They don't require as big of cages, but I wonder about how much the bird will be out? Short of that, maybe he didn't like the Grey and you could introduce him more to the parrot you want? But it sounds like his mind is made up. Take the compromise so you both can be happy and stay together.
Also, I'm sorry about your grey. So few people understand the bond between a parrot and their person. We are the lucky few.

My family: "Emmi" Green Cheek Conure (12/15/2012), One husband, two step kids, and one baby boy born in January 2015!