Casey Quinlan describes improved portrayal of bisexuality on TV. I never watched most of these shows , but you may find it interesting.
... in the 2013-2014 TV season, there are just 24 bisexual recurring or regular characters on all of primetime TV, and 18 of them are women. Look closer, and it becomes clear that even in that small group, portrayals of bisexuality tend to be unrealistic.
... some breakthroughs have taken place in the past few years, however small they may appear. The quantity isn’t there, to be sure. But the quality of bisexual television characters is, on the whole, improving.