Look, tell your therapist how she really is. They will listen, and your 24, shs got no right to barge in and see your therapist. Theres a thing called patient confidentiality and she cant breach that. And its not good for you that shes sees them anyway, and do not let her.
It saddens me that shes homophobic. It really is so sad that she has to have that attitude. It sounds to me from the post you put yourself down, and its a reflection of her actions is why you are feeling this way.
You are absolutely right, shes toxic and in order to deal with toxic people (yes even your mum) you have to cut them out. Job, place of your own. Its scary of course, naturally, but omg you will feel so much better and feel more free to be the real you, and meet the people who deserve to be in your life and actually enriches it.