It is one thing to "tolerate" difference.  It is quite another to play along with a person's mental delusions about their identity.  I "identify" as Barack Obama, the former president of the United States. You should tolerate me--perhaps even get me psychological help. It does not entail you should enable my delusion by playing along and calling me "President Obama." 

By the logic you treat transgenderism you should be calling be "President Obama. Not only that, I should get surgery to darken my skin, change my hair and voice so that I look like President Obama. 

People can identity however they want.  We must tolerate the differences. I don't see any obligation on me, however to play along with their mental delusions about their identity.  Liberals, apparently do.