Was I right to tell my friend off for seeing another guy behind her guy friend’s back?

Now my friend has a guy friend that is madly in love with her. I mean he is crazy about her! She knows he’s in love with her. I TOLD her get in love with her but she never believed me. She kept telling me they’re just friends but that’s not what I heard. Even some of our friends know he’s in love with her. After all the bad dates and horrible boyfriends she had (mostly the jocks and good looking men) she decided to give him a chance. Like FINALLY!
He may not be the best looking guy but he has a big heart, cares for her, honest, kind and he tries to impress her.

Anyways she agreed to go on a date this Wednesday night as she told me he asked her out for the 100th time. He asked her last week and she finally gave in. Man, he was super happy. I’ve never seen him there any other girl at all. He went to the dance with another girl one time, but he kept looking at my friend. What really made me mad is that she told me she met a guy at her cousins birthday party and they started talking and I exchange numbers and started to talk and he asked her out on a date this Saturday and she agreed to it, but I reminded her that she can’t do that because she’s going on a date with her guy friend REMEMBER? She was like oh yeah well with her guy friend, it’s just a friend outing. but she really likes the other guy. I cannot believe her. I told her off that every time a guy that shows a lot of interest and so sweet and genuine like him. She always screws it up. Her girlfriend is so happy to go out with her but she’s gonna break his heart if he finds out she’s going on a date with another guy. I told her that she is playing with her friend’s feelings, getting his hopes up way too much and going to break his heart. I told her he’s gonna be really hurt when he finds out you’re seeing another guy and not only that the other guys going to be her about her going out with her guy friend too. I told her I hope she’s happy about what she’s doing. I told her she’s being a bitch. Am I wrong?

Updates
10 mo
She knew what he asked her if she’s gonna go and wanted me another guy and agreed to go on a date with him on Saturday when she’s going on a date with her guy friend. She’s a two timer. I know they’re not a couple, but she knows the boys madly in love with her. She’s very lucky to have a man like that in her life.
Was I right to tell my friend off for seeing another guy behind her guy friend’s back?
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