Teazle, I am just sending you a big hug. It's just so unfair and I am really sorry.
My own journey in relation to bras has been slow and long and I ma not there yet. I went to a Younger Woman's Forum and heard a lady called Kelly describe the impact of her mastecomy on her, until I heard her talk, I had given up all hope of ever finding a suitable bra (as my other breast is 'new, I don't even know what size I am), but what I learned fom her is that you just keep trying. Unfortunately, its not cheap, but no point me getting on my soapbox about that.
Many people use Nicola Jane, I went to their London shop and though they were lovely, I found it very depressing. Some swear by genie bras- they don't work for me as my prosthesis is too heavy. I use Swetty Betty Ultimate sports bra as it has pockets so I can just slip my comfie in. Its the best I have tried so far, though not cheap, its been worth every penny as it has helped my confidence no end to be able to wear clothes more confidently.
I have also been told that 'about the girl' is good (BCC, please don't delete this as in a way it was through you I had heard of it!) The bras look lovely- again expensive.
I have heard that BCC run lingerie evenings, and I am going to go to one though it has taken me a long time to get to this point.
Rattles