Sorry to hear things did not go well, but it seems like you had an awareness that he may need to act (you said you get why). I know it doesn't change the way things feel. Maybe it can be something that helps build trust in the long run, like knowing he will act appropriately even if it goes against what you want. (I'm thinking hospitalization if you are an immediate risk to yourself, or something along the lines of getting you out of harm's way if you are a minor)...
can you have a conversation with him about feeling betrayed? It may lead to better understanding on both sides in the future if you still end up seeing him after this. I was once sent to the hospital after a misunderstanding. After being sent home from the er and seeing the provider again, we talked about what I was trying to say and what she heard me say. We talked for a long time and got to a better place of trust... it really sucked at the time, but in the end it better. I found out she actually cared about what happened to me instead of just being a paycheck.
Anyway. I'm sorry you feel so betrayed. (Hugs) it really sucks when that happens and I don't mean to minimize the hurt by saying all that. If it helps, you can talk about it here.