tgb wrote:Peter realizes he's home and is back with Olivia
He's not. The current events in Fringe take place in an alternate timeline. Olivia's memories from the original timeline are bleeding over, but they aren't for any of the other characters. It's technically not the same Olivia. For all intents and purposes, the people Peter know no longer exist. He won't be satisfied with that in the long run.
There's a lot of pain and death being caused by the changes to the timeline, and Peter lost a child in the process. It's likely he'll want to revert back to the old timeline at some point, and that might not happen this season.