Dear Katya,
I've been meaning to write to you for a while. I wanted to say a huge thank you for the way you supported me during the last few months. I really don't know what I would have done without you.
Work was so difficult then: my manager was putting me under pressure, and I started to doubt myself. Every time I spoke to you, you listened patiently and never judged me. You sent me encouraging messages when I felt low, and you even came round with dinner one evening.
Your advice helped me to see things more clearly. When you told me to speak honestly to my manager about the workload, I was scared, but I did it, and it really made a difference.
I'm happy to say that things are much better now. The project is finished, my manager has hired another colleague to help, and I finally have my weekends back.
Let's meet soon, and please let me do something for you in return.
Love,
Maria