It's interesting that you spent time on a children's ward to keep safe. It's surprising you didnt get admitted to a psych ward at that point really. How recently has hospital been mentioned? Maybe you need to have a good, honest talk to your care team about how things are at home, whether there is any more intensive support available in the community and whether they feel that hospital is really the best option for you (as although it has its advantages it also has disadvantages, and isn't a fool proof method of keeping safe).
I can understand how you would be upset about your cbt calling your mum, but it is only because she has a duty of care and if you are under 16 (or actually for all intensive purposes 18) then if you are felt to be a risk to yourself they have to inform your parents. Its hard though, and having had similar occur when I was 16 (my GP rang them to tell them that I was suicidal and that she was concerned about me and had sent me for an urgent camhs assessment) I can understand your frustration.
Is your Mum being offered any support in relation to your issues and how best to support you? Do you think that might help?
Take care, try and stay safe....there is usually people around on here ( crisis room/ here n now room) if you need to post for support and there are lots of distractions and games around on the site. Theres also the samaritans/childline if you want someone to talk to. Theres a way through this