You have my deepest sympathy Lilith_82 I've suffered from something very similar myself so I know just how painfull it can be.
I know this may not be appropriate in your case so get advice first before you try it.

When I was really bad with it my doctor and physiotherapist both advised me to kneel on the floor and bend forward to rest my body on something comfortable (a little like you get when doing it doggy style) just to take some of the strain from your back. It helped me, if it is ok for you it may help a little.

__________________
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If not an excuse for death,
and what is death,
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