The very first time I saw the crying clip I thought I heard Brad say "I can't let her go". I could be wrong. Personally I think
1) The SC is after Chantals MTP date and they are all talking and the family is leaning towards Emily. Brad is defending C (b/c he is torn and feels bad) he cries b/c he feels like crap letting her go etc. As the viewer we'll think he's picking C now then we'll be "shocked" when he still picks Em
2) Em tries to leave early and he's crying that he can't let her go before he has a chance to tell her he picks her (this can also be why he tells his brother "I'm thinking about not picking anyone again"
3) He is crying b/c Ashley left...he tells both F1 and F2 I'm sorry but the wrong girl left ( this could also go with the "not picking anyone again" comment) shocking everyone. He heads back to the states for Ashley and it ends with a proposal wherever she lives!
I hope it's the first scenario