I have many friends who choose to play an avatar that’s the opposite of their gender IRL. However, NONE of them carry out romantic relationships without informing their SL partner first, of their RL gender. I think that’s the best way to be, even if your partner is infatuated with your SL pixels, they deserve to know. Let them decide if they want to carry on the relationship, don’t decide for them. Truth is best, don’t you think?