Wow congratulations on the forthcoming motherhood
After seeing your T for so long, I am sure it will feel really hard finishing with her, I guess like a bereavement.
Have you been able to talk to her about it? I know my T has said that endings are really important to work through and yes as someone said above, if you don't continue with this T, maybe seek out another to support you in your transition.
Good luck with the rest of your pregnancy - children can being such new perspectives to life.
Soup