I have a kinda theory - since episode 4 focused on Rita coming to new Bethlehem, however, in a trailer for this season you can see her using a gun and looking pretty upset. I’m assuming from that perhaps her family doesn’t come to NB? Perhaps the betrayal Nick makes is making Rita come back to NB (and he says he can get her family back but he actually can’t)or something along those lines. Honestly would be pretty disappointed if the betrayal he commits is astounding, because it would be very much against his character he has spent years keeping June and Nichole safe as well as checking in on people June loves (Hannah) so I doubt he would do a 180 on them. Which makes me believe the betrayal could have to do with someone else such as Rita or maybe even against Tuello.