It depends what you mean by "trust." In some ways, I trust no one. I know that anyone can betray anyone.

I was betrayed by my previous therapist - who I left because of that betrayal (although more because of all the dynamics that led up to the betrayal) - but my position that no one is completely trustworthy predates her - and I was shocked that she betrayed me, as I totally trusted her in action.

Despite the fact that I believe no one is totally trushworthy (not even me, not even for myself), I choose to trust, or to act as if I trust, and then trust that if my trust is betrayed, I will be able to handle it, because the alternative of trusting no one seems to me a much worse life than trusting judiciously, knowing I will be betrayed at some point.

Do I trust? I don't think so. Not really.
Do I act as if I trust some people? yes. And I am better for it.

Did I act as if I trusted my current therapist immediately? Hmmm. probably pretty much, although the trust has grown from substantive topics to the process. I also did a lot of research and interviewing so had some information about him, and about our rapport, before I first saw him.

Or perhaps I am parsing words.