How can I keep my boyfriend from my Mother? Please help!?

Ok, so I'm 15 and I'm going out with a 22 year old. Ya, I know, pretty big age difference.... aanyway, I haven't told my family or any of my friends about him because I wouldn't want him to get in trouble with the police... but tonight my Mother took away my cell phone because of a reason that I wouldn't like to go into detail about... anyway she took it up so quickly that I couldn't even tell him that my Mother was taking up my phone, and not to text/call me until I get it back. So guess what happened..... That's right.... He sent a.... rather dirty text... to my phone.... and my mother read it. She was extremely ferious at what he had said.... so she decided to call him and cuss him.... but I stole my Brothers phone and told him not to answer if my phone calls him. He didn't answer....thank god! The reason I would rather them two not have a conversation is because once my Mother relizes that he is 22, she would call the police on him, no dout about it. It has happened before with another guy. I really just want my Mother to leave him alone.... but now she is going to do whatever it takes to find out his life story and evenutaly put him behind bars.... I feel so bad.... if I would have just have never have spoken to him the first place... he wouldn't be in this mess.... anyway... I can't just stop talking to him.... we have grown attached to eachother.... if that makes sence.... He is so wonderful, and sweet and I might actually ...."love" him... but then again... I'm just 15 and this may be what some people refer to as... "puppy love" but I still just want him to be safe and the LAST thing I want is for him to be behind bars.... Now.... what I'm wondering is if any of you people know anyway whatsoever to maybe get my Mother to just leave him alone... and NOT ask him his life story/age... do you know ANY way I could get my Mother to forget him? Any ideas at all? Please! I NEED HELP!!!