should i call my friend her or him?

[Hayley]

basically my friend decided that she wants to be a boy and posted on twitter that she wants to be called Alex. she has never told me that she wants this (i knew threw twitter) but some of my other friends occasionally call her Alex. im really not sure when im referring to her if i should say he or she, it doesn't bother me at all or affect our friendship, after all why should it? but it just doesn't feel right when ever i call her him or he etc. i want it to sound natural but it just doesn't not sure what to do

[Becky]

Maybe ask this person and ask whether your friend wants to be called he or she (maybe talking about it will settle you down and make it feel natural?)