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This is definitely not just fallout from the loss of our son, I was feeling this way before we lost him - getting pregnant was really not a good idea to be honest. But now our baby is gone, I don't see any reason to stay. If he had been born I would have tried my best to make our marriage work for the sake of the baby, but I know deep down that would never have worked in the long run.
I have had counselling to help me with the loss of my baby, and told the counsellor I was not happy in my marriage. He turned out to be a Relate trained therapist and he told me that he sees this quite often - one partner who is desperate to leave and once that happens there is no going back and all he can do is counsel the remaining partner to deal with the end of their relationship. I realised that I could stay with my husband and be desperately miserable for the next forty years, or strike out on my own. He won't let me go though, and it's frustrating. I felt trapped when we were still together, and now I feel even more trapped because he knows I want to leave and he won't let me.