Two things awesome here:
First: Definitely awesome that your grandmother is an ally! Be patient with her and she will come around. The pronouns may take time, since folks tend to get set in their ways. (I knew a wonderful Nun who STILL used them derogatory term "darkies" right into the 2000s, she loved her Indian neighbours, it was just a term she knew!)
Second: Anti-Depressants. Well done. Taking care of your meltal health will help keep you afloat and make the dark days a little lighter. I have been taking them myself for pain related issues, and they are a great help to me.
Keep your head up and be proud of yourself. Enough small steps and you'll be amazed at how far your journey takes you!