This may sound extreme or even silly, but I agree.
My DH wouldn't let us get a dog in the 25 years we're married, said absolutely not, he'd put it out on the street if we got one, because he was afraid of the responsibility (like having another baby) and also vet expenses. I've wanted a dog my whole life, and my father said when I get my own house I can get one. Well, I have my own house (yes, shared with DH), but I STILL wasn't allowed to get a dog.
Well, 9 months ago, I put my foot down. I told DH I was going out and coming home with a puppy. I'd been searching for one without him knowing, and found one I fell in love with. He threatened me with putting the dog out, and I said "just try it" and left the house.
Two hours later I had my puppy in my arms, brought him home, and DH didn't speak to me for a couple of days, and wouldn't acknowledge the pup at all.
NOW, 9 months later, he is in total love with that dog, and would probably put ME out before he put the dog out.
He sees how much I love my Brian, how the pup has brought joy into my life, and is like my own child.
Give your DH some time, stand up for your love of the dog, let him see how much the dog means to you and that you'd be brokenhearted if you had to give him up. Show him that you take good care of it. I'll pray that he comes to his senses and puts your happiness before his own stubborness. Good luck!
It's hard to see since I took it with my cellphone, but this is my DH holding Brian while both of them watched a ball game. Yeah, right, he didn't want a dog!