Hiding from my mom...feeling guilty

Ive been dating my boyfriend for almost 9 months now. He's so amazing and fits me perfectly. Other adults and people in general tell us how great we are together in every way. I'm 16 (17 in November) and he's 17.... but the problem is my mom. My mom is extremely overprotective and over reacts for everything. I am an only child and she has never raised a teenager before so she doesn't understand a lot of things that teens my age go through or do. We are pretty close except for the part where I tell her certain things , which is bad and i wish it were different. I want her to understand me more. She knows I am very mature and that I am a good teen but I know she wouldn't want to hear that I am dating. My mom loves my boyfriend as my friend but she really doesn't know.... Because she just went through a terrible divorce with my father, she thinks all men are bad and tries to make me think that way. I am so stressed out because I don't want to hide from her anymore. She has asked me twice his week out of the blue , if I am honest with her about everything. I want her to know the truth and more about me but it's just so hard because she reacts to things dramatically. Also I already met his family and I see them all the time , but he gets upset when he can't talk to my mom.😪