For those of you who have had ups and downs in your relationships with your Ts, what generally causes the "up" phase?

My relationship with my T has improved lately, and therapy doesn't negatively affect my life as much as it used to. The cause of this improvement seems pretty minor--he started responding to my texts and emails in a timely manner (not that I text or email him much), and I feel I'm allowed to text/email him occasionally when I have a good reason to do so.

It's strange that such minor changes can make such a big difference. I'm curious about other people's experiences.