I feel similarly, I'm really going to miss this show, but at the same time it feels like it's the right time to end it.

Nina should 100% be back for the finale, Julie Plec has always been very definite on how Nina has said that she will definitely want to return for the finale to bring closure to Elena. She still seems pretty close with them all, reportedly she also filmed a quick voice-over for them at the end of season 7 when Damon hears Elena's voice