Lots of people use real places from memory as their safe place. I don't see anything at all questionable about it. What's important is that the client feels control over the process and chooses where they're most comfortable, whether that mental retreat is a concrete or abstract one. I wonder if she was fishing for clients too.

Sorry you are struggling!

It's hard to predict what will come up when we discuss the past, so... I don't think your therapist or you could have predicted the exercise might backfire and it sounds like you had a number of other factors actually contribute to your crisis. It's just really really important to focus on stabilizing right now so you don't have such a strong reaction going forward. We who've dealt with trauma have inner minefields sometimes, and sometimes... we have to map them the difficult way.

And yes, I'd mention it to her if the memory you chose was triggering.

Her focus on getting you grounded now is just right.