I have these fantasies about holding hands and going on a date with a friend of the same sex, and on rare occasions, I imagine us cuddling or just spending time together. Am I bisexual?

There is a pervasive idea in society that you are either "heterosexual" (100% straight), "bisexual" (50% straight/50% homosexual) or "homosexual" (100% homosexual/0% heterosexual). However, I like to think of it more on a continuum of sexuality, which is flexible. It can stay the same over time, but more often than not sexuality changes over time. It might even go back and forth (for example, men and women "experimenting" for periods of time in their lives, but losing interest later on)

I am a female in my twenties. I would say that I am 92% heterosexual (8% lesbian). This is because I find males sexually attractive, but cannot deny that I do find many women attractive as well. I went to a strip club once (never thought I would end up doing that!) and found myself being turned on a bit, mostly by the girl's confidence. I'm not interested in engaging in romantic behaviour with any female, and definitely know my preference for males is dominant. 

I'd also like to point out that thinking to yourself "I should have a body like that" doesn't necessarily make you bisexual. Females are conditioned by society and the media to "want" what they don't have in terms of looks. Sadly, women compare themselves to other women almost constantly on an unconscious level.  If you ask your friends, they may admit that they do the same thing. 

So rather than limiting your sexuality to one of the three boxes, embrace your sexuality and figure out where you fit on the continuum. It may allow you to feel more comfortable with who you are and how you are changing and growing as a human being.