What do you do when your partner doesn't trust you?

Talk to them and tell them how you feel. Try to be honest with people. They only want the truth. If that backfires, try to give an example of what you are talking about. That way it makes them think about what they have said. If that still doesn't work, ask the teacher if you can get partnered up with someone else. Tell her or him why you are upset. Or ask to work alone.