If you have a history of SI from before your current T... at what point did you share that with your T?

I'm struggling to figure out how "important" it is, if it at all. I am not currently SI-ing, but had some urges after our 3rd session. Thankfully, he picked up during the 4th that things had had been rough for me and figured out we need to go slower. (Big points to him for that, because I wasn't getting it.)

I'm worried about being terminated (yup, had a different therapist that after 3 sessions kicked me out - I think b/c I was upfront about the ongoing SI at the time. It sucked!) Also nervous b/c I think I'd need to write this out too (rather than being able to say it), and just wrote out other stuff for him last week... so feel like I'm turning him into a penpal-T.

And I worry that it's not really important, or that he'll want to talk about it, and talking about it will increase the urges.