I feel disheartened Did I do the right thing?

I told my friend her boyfriend was on tinder even though we was not friends I thought she had a right to know as he was messing her about previously. The next day her boyfriend sends me a message on social media saying mind your fucking business before I cause trouble for you and your family also before I knock on your door. I then rang him he didn’t answer I rang him twice no answer so replied saying ‘lol’ he replies saying I don’t entertain stupid people that’s why I’m not answering blah blah blah. I just ignored the message as if he really wanted to he would just have answered if he was the badman he makes out to be. She was my friend for such a long time and even tho I told her when we was not talking I sent her a message saying saw you told him what I told you. She goes ignore him. I didn’t reply to her message also as I thought to myself wtf but is it me or has she chosen a man over her childhood friend? Considering he cheated on her twice previously. I feel really disheartened by it all.. was she really a friend all this time or
I feel disheartened Did I do the right thing?
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