Thank you everyone for your replies. You make some very good points.

It is easy to forget that what we see online does not give a full picture of the reality of someone's life once we are caught up in these feelings, so thank you for reminding me of that fact.

With me, I think it's not only envy but feeling excluded from T's life...(I've just realised, it's not T's life that I want to be a part of really; it's the things she has that I feel excluded from - happiness, love, success etc.)

I too have had a few acquaintances who I was shocked to find out were part time Ts as well as doing their regular jobs. The reasons I was shocked to discover this about them varied but the common theme was that all caused conflict in the workplace, upset others with judgemental attitudes and afterwards were completely unaware of how their behaviour affected their colleagues so I can believe that Ts are not perfect but once again, this escapes my mind when I'm caught up in the thoughts and feelings I describe.

For some reason, it's as though I WANT to maintain this idea of T's life being perfect. It's like I want to torture myself over it, even though I hate the feeling. I think I need to stop googling but for my own sake, not for T. I disagree that googling a T is stalking. Driving deliberately past their house or following them home from their office would be stalking but reading information they have chosen to put online and which they know anyone can have access to is not stalking or "wrong" in my opinion.