I'm going to bring up my friend's ex-girlfriend in a context that he said was okay
Is your friend going to be fine with this?
I don't care about his opinions, because his ex-girlfriend is so much better all the other girls
It's not nice to bring up someone's past romantic history if it's upsetting. You should respect your friend a little more.
Nah I don't care.
Well it may be something that really upsets your friend so you should do your best to be weary with how you approach this. I would assume that you would want to try your best to not harm this friendship that you have.