Having two Ts is difficult. I did that once when my T went on an extended, couple month vacation; found an online T to work with for only a tiny piece of the puzzle that T and I weren't working on anyway (writing about my recurring dream theme) but I told T about the online T immediately when she returned and T asked me to end with online one.

I guess if I were you I would bite the bullet and tell T1 about T2 (not the details or specifically why you got T2) and I think I'd be a bit of a coward and imply that I had been seeing T2 most of the same time and seeing two was now difficult instead of helpful and you think you are going to go with T2 because of cost, insurance, location, throw in all the business reasons you can think of? Then, hopefully, he'll have something to say in terms of how many times he thinks you should see each other again or ask questions, etc. and you can go from there.