I really sympathise - my cocker pup was a total nightmare and would reduce me to the point of tears fairly regularly - OH's hands were scabbed and bloody for what seemed like ages (he plays with her using his hands much more than me though) - but we taught her bite inhibition over a period of a few weeks and she is a joy to be around now (most of the time!). We didn't resort to using the crate as a timeout, we foudn it was enough to exclude her from the room we were in for a few minutes.