I can't imagine the pain ever going, but I know that one day I will be able to think of Gari without breaking down. I talk about him constantly and still have his bed and his toybox sitting out for visiting dogs to use. I had my friend's 2 Cockers staying from Saturday until yesterday, and they were a great help, although we were still wishing Gari was here.
Benji will live on in your heart and your memories, like Gari will with us, they will always be with us because we love them so much.
I'm sorry your OH isn't being supportive, but it sounds as though he is grieving too and doesn't know how to show it. I know my OH is heartbroken, he talks about Gari all the time and cries a lot, which I never expected, and is desperate for another Cocker to come and share our home, although we know nothing can replace Gari.
Think long and hard about getting another dog, and if you think it is right for you then do it, you will never look back. You will love the new dog just as much, but in a different way from the way you love Benji.