Thanks for writing into Alterheros! You seem to be having some confusing feelings about whether or not you are transgendered. You mention that you have always aroused yourself by fantasizing about being a woman in a sexual encounter with a man. Even though you are attracted to women, you find it hard to have a physical relationship with them. Furthermore, you develop a sense of jealousy and a desire to be a part of social conversations about girl talk'.
In general most transsexuals feel a persistent desire to be the other sex. By the classical definition, transsexuals feel like they were born into the wrong body and feel a vast difference between their thoughts, mind and their bodies. Other terms surrounding this area are bigender (embodying behaviour of both genders, interchanging one for the other at a particular time or scenario) and genderqueer (not identifying with either a male or female gender or identifying with both at the same time). I realize these terms may be new to you so feel free to explore them further.
With respect to your sexual fantasies, it is normal to have certain arousing thoughts that may not necessarily reflect who you are. It could also relate to a favourable sexual encounter you wish to partake in. For example, since your fantasy includes you participating in sex as a woman, perhaps creating a sexual experience where you have the more feminine' role (in what ever way you define feminine) and your partner performs the act of the man'. This is just one interpretation, it is up to you to create and explore your sexuality in this context.
You mention that when you picture yourself as a woman, you focus more on my visual aspects, smooth legs nice curves Do you feel that only women can have these attributes? Yes, the common ideas and societal expectations of women include those features, but you can find many individuals who do not feel like they need to conform to the socially accepted view of what gender should look like. Some men have long, styled hair, painted nails and even shave their legs. When in a social context where girl talk' is brought up, the social stigma of men not being able to embrace their femininity may hinder you from taking part in that discussion. While some people may be taken aback by your interest in this topic, do not feel like you should be excluded.
While I made mention of all sorts of different types of labels and categories, they are totally optional. There are people who feel like they need to identify with one group or another in order to feel comfortable. More importantly, there are others who do not find the need to label themselves or their actions in a particular way. They opt to be more fluid and flexible with their life and their relationships with others. If you are struggling to find your identity, do not feel pressured to find an answer immediately. Your whole life is ahead of you to experience new things and to make new discoveries about yourself and your sexuality.
Here are some transgendered related resources if you wish to read more about it:
Kelley for Alterheros