Speaking from recent experience it is heart breaking to watch your baby suffer. We're thankfully are on the other side now... I don't know if you saw some info that I posted here last month, but I swear by Secura Protective Cream! Within a day Caitlin stopped crying when she wet or dirtied her nappy, she was a different girl! Even if you were to use the cream on its own without the other bits I mentioned it could make a difference.
Within three weeks of using this cream (and the cleanser and spray) we went from approximately 2 by 1 inch ulcer to completely healed skin. The H has started to involute but it is very, very slow. A word of warning - we've just survived a week with a stomach bug and the constant dirty nappies started a few new bleeds. Luckily we kept using the secura cream and they didn't come to much, no new ulcers like we would have expected before. So we're stocking up on new supplies just in case. At the very least its great protection against nappy rash.
Best wishes to you and your family