In a way I can completely understand why Kenzi wanted to go. She's been through so much, she's gone through so much, and she's a mere human amongst the Fae world. After sacrificing herself, died and then being returned, it's totally understandable her feelings about wanting to get away, of wanting to experience life. Someone who died and came back, there is a certain revelation that comes with that about knowing what else there is out there, all the other opportunities that could await her. She loves Bo, Tamsin, and everyone else, but in her mind she needs at least something for herself. She needs to figure herself out, figure out what she needs to happen in her life. Obviously she will always be beside Bo, but she needs to be someone other than just the human sidekick of the unaligned succubus.
At the same time though, it sucks that she has to leave Bo behind. They are found sisters in a found family of outcasts and misfits, they found each other when they were both lost in the world, and became stronger with each other by their sides. Bo and Kenzi are the backbone and heart of the show. Plus, it's the last season. Having Kenzi-less episodes aren't going to be the same.
Which is why I'm certain she'll reappear again, perhaps not in the next several episodes, but definitely when Bo needs her the most. Because they are family, and because the show began with them and therefore it should end with them.
Furthermore, I'm glad that they're moving things along with Bo's father, at least giving more insight of what could possibly be around the corner of the big finale. It'll definitely be a standoff between them, and even though we haven't seen his face yet she definitely has made contact. And making things interesting with bringing in Persephone, a.k.a. her stepmother, and some more backstory on her parents, basically confirming what her mother had already stated to her previously about being held captive, but now we have more background about where Bo was born, which was basically Hel. Also, what does it mean when Bo lit that candle? What is going to happen? Is she summoning an army? Or was that a sign about something else entirely? I'm not quite sure just yet, but that ending certainly left me wondering what is going to happen, and how will Bo officially meet her father.