Is it possible to be a male lesbian ?

I know this sounds like a joke, but I'm a person who having always considered themselves straight in their orientation, in what they fantasise about etc, etc, am baffled by the amount of homophobic comments and abuse that I get out on the street or public transport, shops etc. I dress pretty ordinarily and don't look particularly arty or whatever might be perceived as 'gay'

This is not once a week where someone might homophobic-ally abuse you in the context of a common-or-garden insult, this is on a daily basis, overheard comments, stares, I've never considered myself gay but I'm sure readers will know what I'm describing.

I have genuinely no interest in men and only think about women in a romantic / sexual context. I have a pretty quiet,gentle personality which can give morons the wrong impression as well.

Can you be a male lesbian, is it possible?