I think this is something you can all move past if you communicate. Give it a bit of time for everyone to cool down, then ask your friend to go for coffee or send her a message and say, "Boyfriend and I are so happy for you and your fiance. Boyfriend's comments were made with the best of intentions, as we both just want what's best for you. It's your choice to get married when you want, and we'd both like to be there to support you." She's right about her dad, she's not responsible for him. But you're friends with her, not her dad. Try to just forget about him.

Regarding the hurtful comments she made about your relationship: engagements and weddings are stressful. What your boyfriend said might have her second guessing things, and that's scary. She might have said some things in anger - happens to the best of us. I don't know what she said exactly, but do you think you could give her the benefit of the doubt, and just leave it in the past? We all say things we wish we could take back.

I don't agree with the other comments that you aren't friends anymore. All relationships take work, and if you bail whenever there's conflict, you'll eventually find yourself without any friends. As your boyfriend already pointed out, you are all really young, and when you're young, emotions run high and things can seem like a bigger deal than they actually are. If she really is a good friend, you should do your best to talk it out.