I just went through this when my T of 5 years told me in mid February that she was leaving the state in late March. I immediately started looking for a new T and found one, after interviewing 3 different ones. For me it was important to start this process while the old T was still around so she could help me decide which new T to choose.
I got really mad at my old T for leaving, but after a few weeks the anger went away and I just felt really sad and annoyed that I had to find a new T.
But now I'm OK with it. The first few sessions with my new T were spent helping me to process the feelings i had as a result of my old T's decision to move.
I hope you can find a new T that you like. It's not an easy thing to go through - I'm sorry that you're having to deal with this.