Try to enjoy your movie. You must understand that you will be ok. I understand how you feel. I've been there. You are getting good advice. Detachment takes time and sometimes anger comes first but it must evolve.
The fear is your Achilles heal. Your wife may divorce you. You will have a wonderful life no matter what if you so choose. Breathe.
I am not spewing platitudes. I wanted to die. I know the pain. I'm telling you, beyond the fear is a beautiful and tranquil place. Still difficult but really quite empowering.
Focus on the movie, whatever movie it is, look for something life affirming in it.
Life is short. Don't give up this time with your bro. Enjoy and appreciate it.