There were weirder and worse ways for someone to cope. Ahsoka couldn't remember if Anakin had ever done such a thing in their dreams. If he had, he'd never shared. Which hurt, but was understandable.
And if he hadn't, she wished that he would have. Perhaps having an outlet for his thoughts that wasn't a Sith Lord might have prevented a lot of tragedy.
"I understand. If you'd rather I leave, I can do that too."