I say, so what if you have "masculine traits."  There are such things as tomboys who still identify as girls.  You could just be that type of person.  There is nothing you can do to change how you feel.  I was told similar things by other people once.  It hurt me a little bit.  You just have to be persistent.  Societal advantages of being a man probably are not going to stop you.  The fear of getting beat up isn't going to stop you.  Once you realize your TG, it is always with you.  99.8% of the time it isn't a phase type thing.  People are always going to state reasons why someone should not transition, or why they could never make it as the other gender. 

I thought for awhile that because I was handicapped I could never be a woman for a reason I do not remember.  It took me awhile to get over things.  Another TS girl that I have been talking to online helped me through my issues.  If it wasn't for her I would still be doubting myself left and right.