Hi Maggie - not sure about the waking problem (I have that myself and find it difficult to overcome) but as for falling out of bed, have you tried a bed guard of some sort - or would it be possible to push the bed up against the wall maybe?
Would this kind of grab rail help at all. My husband has one to help him stand up from the bed but it might be enough to stop a fall out of bed. This isn't the one he has as he uses a hospital bed. The one he has is fitted to the hospital bed. It's the same idea though.
I'm hazy on the names of the various different payments but know there's a higher rate for one of them (Attendance Allowance?) if the person being cared for gets up at night. Are you claiming this plse?
The extra money may be enough to pay for overnight care occasionally so you can catch up on your sleep. I can't imagine how dreadful it must be to be woken every night and to sleep very lightly because of worrying about the cared for person's safety.