I was wondering why you find Ten taking away Donna's memory as violating her? She would have died if not. We don't know if she would have rather died with her memories than lived without, but Ten had to make a decision at that point and there was no way he was going to let her die. It's not as if he bragged about his plan to do so, much like Twelve did. The difference with Twelve and Clara is that Clara was already dead, he had already screwed up by saving her before the Raven.