How can I ask my my mom to put me into therapy?

I'm 16 and I've been struggling with depression since I was 12. I was bullied all through middle school and in some parts of high school (a lot of it is little whispers when I walk into a room and 'jokes' to my face and fat jokes) I've also been having an up and down struggle with bulimia and cutting. My mom recently found out about my cutting and thought I was doing it for attention and last night she found out that I've been crying myself to sleep and she offered therapy and I declined it, because I knew she wouldn't want me in it. But this morning I started thinking about it and I realized that maybe it is a good decision to go to therapy (mainly because I'm afraid if I don't I'll end up killing myself). My mom is kind of on edge right now and even if she did offer therapy, she'll probably freak out. (It's weird I know) How can I ask her without her freaking out?