Ted has a selective dark humor. He wouldn't want to joke about most other people, nor things that are a bit too close to reality for comfort. But if it's far enough remove from reality, then it's safe.

They go on to discuss other random things for a while, and Ted feels a lot lighter after having the conversation. After that, Shaun arrives, and Ted has to hang up.

He doesn't call Joan in the evening, but he does text her a goodnight message. He just doesn't want to become entirely dependent on her comfort and distraction to be able to sleep. He does wake up from a nightmare at some point, but manages to calm himself back down and eventually fall back asleep. It's progress, if only a little.