Bro In English Please

As I was walking back from the gym today I heard the worst conversation I have had the pleasure to eaves drop on. Let me walk you through it. Three men. Guy 1, guy 2 and guy 3.
Guy 1 "Bro, sorry to hear about your father."
Guy 2 "Bro, oh Bro. Thanks Bro."
Guy 3 "Bro, I'm so sorry. When did your father die Bro?"
Guy 2 "Bro, I can't talk about my father. Bro, bro, bro. Bro. Let's talk tomorrow"
[please note that Bro is actually pronouced like bra]

All of this in the few minutes I walked past. What is happening to the English language? I think I may like to start my own trend and use sis, or mama, or hella' fine b*tch. If men can use bro - why can't I use some female version?