Watch video Here   With the release of the final instalment of the hugely popular Twilight franchise, actor Peter Facinelli says he's left with a "bitter-sweet" feeling. The 38-year-old actor, who has been involved with the series since it began in 2008, makes his final outing as Dr. Carlisle Cullen in The Twilight Saga: Breaking Dawn - Part 2. "Good things kind of have to come to an end at…