First off, it shows what kind of a friend you have. That's jacked up. Any friend that would pick a boy over you is not a real friend at all. Boys come and go, and there will always be more. But a real friendship should last forever. Shame on your friend, and the jerk boyfriend.
Wow.... what kind of friend would that be, and what a loser boyfriend. I just wouldn't be ok with that, because you are betrayed by two people that you really trusted. I just think if someone would do that to you, then you didn't mean a lot to them in the first place. Even though it's the hard way, it's better to find out how people really are.
Hell yeah that would hurt me! Your trust with him is not only broken but also your trust you have with your friend is broken as well. There's things that girls shouldn't do with another girl's boyfriend especially if they're one of your girls. If they both want to act like that then they're definitely two people you do not need in your life anymore. They're pollution to your life pretty much.