Grief is the hardest thing to have to cope with and the guilt is part of it. Oh dear, 9 in a year, thats terrible. I lost 3 last year in 4 months and it broke my heart.
I know it feels like everything goes wrong at the same time and it's impossible to cope with. I don't blame you for being heartbroken, you are human afterall. Please be kind to yourself as you grieve, you are clearly a loving and caring piggie parent as you chose to give them all a good life and all your piggies are lucky to have you.
I've made the decision to have no more piggies now. I have Ruby and Delilah left and after that I want no more pets, it's too hard to handle when they become ill and sadly pass away. Mine have all been tragic aswell and it scars you for life doesn't it.
It's ok, you are not bringing anyone down. I think chatting with someone else who understands helps. Your right, they really are amazing little souls