To answer honestly, I think that your feeling you need to be there as a support for your T takes away from what you should/could be getting from the therapeutic relationship. In a way - like a doctor asking you if you can look at her broken leg.
The bottom line is that it should be very clear that the T is there to support you and not the other way around. I know that for me, therapy offers the direct support that has been missing from my life. (example) For awhile I was watching the clock closely. I didn't want to be a burden on my T and go over time. She told me not to do this. It was not my responsibility.
One crucial thing comes up (in my mind). T's (often) simultaneously have their own T's in order to be in good shape to be treating patients. In addition, they (often) have a network of other T's to speak with. This is where their support source comes in as I understand it.