I think it's important to be able to voice your opinions, questions, feelings, etc. about anything that occurs or has occurred in your life - including the things that occur in the therapy room, between you and your therapist. It's your therapist's job to provide a space where you can be authentic, model non-defensiveness, curiosity, reality-checking, and accountability as part of conflict resolution, demonstrate that the relationship can withstand anything you bring to the table, and show you that breaches in the relationship can be repaired. That's a pretty tall order - but in my opinion, how a therapist responds to the situations that occur between therapist and client is part of what separates great therapists from good, or even bad, ones.